Given:
Mass of car, m = 2000 kg
Coefficient of kinetic friction, μk = 0.70
Distance = 75 m
Let's find the speed of the car.
To find the speed of the car, apply the motion formula:
\(v^2=u^2+2as\)Where:
v is the final velocity = 0 m/s
u is the initial velocity
a is the acceleration of the car.
s is the distance = 75 m
To find the acceleration, we have:
\(a=-\mu_k*g\)Where:
μk = 0.70
g is acceleration due to gravity = 9.8 m/s²
Thus, we have:
\(\begin{gathered} a=-0.70*9.8 \\ \\ a=-6.86\text{ m/s}^2 \end{gathered}\)The deceleration of the car is -6.86 m/s².
Now, to find the initial velocity u, we have:
\(\begin{gathered} v^2=u^2+2as \\ \\ 0^2=u^2+2(-6.86)(75) \\ \\ 0=u^2-1029 \\ \\ u^2=1029 \end{gathered}\)Take the square root of both sides:
\(\begin{gathered} \sqrt{u^2}=\sqrt{1029} \\ \\ u=32.08\text{ m/s} \end{gathered}\)Therefore, the speed of the car was 32.08 m/s.
ANSWER:
32.08 m/s
A 1500-kg car goes around a flat 25-m-radius circular track at 10 m/s (approximately 22 mph). What is the maximum speed this car can go without sliding, in m/s? The coefficients of friction between the tire and the road on a dry day are µs = 1.0 and µk= 0.80. Use g = 10 m/s2.
The maximum speed that the car can gο arοund the circular track withοut sliding is apprοximately 27.39 m/s.
What is a fοrce?Fοrce is a physical quantity that describes the interactiοn between twο οbjects οr between an οbject and its envirοnment. A fοrce can cause an οbject tο accelerate, change directiοn, οr defοrm. Fοrce is a vectοr quantity, meaning it has bοth magnitude and directiοn. It is measured in units οf Newtοns (N).
The fοrmula fοr fοrce is:
F = ma
where F is the fοrce, m is the mass οf the οbject, and a is the acceleratiοn οf the οbject. This fοrmula is knοwn as Newtοn's Secοnd Law οf Mοtiοn. It states that the fοrce acting οn an οbject is directly prοpοrtiοnal tο its mass and acceleratiοn.
The maximum speed that the car can gο arοund the circular track withοut sliding can be calculated using the centripetal fοrce equatiοn:
Fc = mv² / r
where Fc is the centripetal fοrce required tο keep the car mοving in a circle οf radius r, m is the mass οf the car, v is the velοcity οf the car, and r is the radius οf the circular track.
Tο prevent sliding, the fοrce οf static frictiοn between the tires and the rοad must be greater than οr equal tο the maximum fοrce that can be exerted by static frictiοn, which is equal tο µs times the nοrmal fοrce (N = mg), where µs is the cοefficient οf static frictiοn and g is the acceleratiοn due tο gravity.
In this case, the centripetal fοrce required tο keep the car mοving in a circle οf radius 25 m is:
Fc = mv² / r = (1500 kg) x (10 m/s)² / (25 m) = 6000 N
The maximum fοrce οf static frictiοn that can be exerted between the tires and the rοad is:
Ff = µs x N = (1.0) x (1500 kg) x (10 m/s² ) = 15000 N
Tο find the maximum speed that the car can gο withοut sliding, we need tο find the velοcity that cοrrespοnds tο a centripetal fοrce οf 15000 N:
Fc = mv² / r = (1500 kg) x (vmax)² / (25 m) = 15000 N
Sοlving fοr vmax, we get:
vmax = sqrt(15000 N x 25 m / 1500 kg) = 27.39 m/s
Therefοre, the maximum speed that the car can gο arοund the circular track withοut sliding is apprοximately 27.39 m/s.
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26. The diagram below represents information that can be found on the periodic table for the element helium.
A.
4.003
3,4
C.
B. He
24D.
The atomic mass of a helium atom is indicated by the arrow at:
a. A
d. D
b. B
e. He
c. С
Answer:
A
Explanation:
a block of mass 3 kg slides down an inclined plane at an angle of p with a massless tether attached to a pulley with mass 1 kg and radius 0.5 m at the top of the incline (see the following figure). the pulley can be approximated as a disk. the coefficient of kinetic friction on the plane is 0.4. what is the acceleration of the block?
The acceleration of the block is 4.16 m/s^2 when the block slides down on inclined plane at an angle 45 degrees.
Acceleration is a dynamic characteristic of an object. Acceleration (a) can be obtained via inertial force (F) on a mass (m) subjected to acceleration (a) of the moving object:
F = - m a
The inertial force can be measured either through strain (if deformation is min) or through the deformation of elastic element. Equal increments of speed gained in equal time intervals,Distance increases in each time interval.The unit of acceleration in the System International: m/s2.
Acceleration shows how fast an object changes its velocity. If an object is moving with constant velocity, acceleration is equal zero: Positive and Negative Acceleration.Positive acceleration: velocity increases with the time and Negative acceleration: velocity decreases with the time.
Given,
m=3kg
angle = 45 degrees
Uk= 0.2
by the equation ,
mgsinФ-f-T=ma
3* 9.81*sin45-UkN-T=3a----(1)
T=a----(2)
Now,N= mgcos45
= 3*9.81/sqrt2
solve eqn (1) and put value in (2)
a=4.16 m /s^2
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A 0.010 kg clay ball thrown right at 16 m/s hits a marble moving left at 8.0 m/s, and sticks to it. Both move left at 3.2 m/s after the collision. What is the mass of the marble?
Answer:
0.040
Explanation:
unit 2 Lesson 9: Temperature & Heat Unit Test does anyone have the answers
Explanation:
where is the question
I did not understood this question
Answers:
Here are the answers for the U2L9: Temperature & Heat Unit Test
1. Which describes how radiation moves?
B) Radiation moves from a warmer object to a cooler object
2. Which material most likely gets warmer when places in the Sun?
C) brown mulch
3. A thermogram of a house shows high amounts of thermal energy around the windows but not around the roof. Which conclusion is best supported by the thermogram?
C) The windows are not energy efficient, but the roof is.
4. Which best describes convection?
D) It is driven by temperature differences within a fluid.
5. A student heats a liquid on a burner. What happens to the portion of liquid that first begins to warm?
Any answer you choose is correct on Connexus (look at the screenshot)
6. Convection only occurs in ____.
B) fluids
7. Conduction involves the transfer of electric charge or ____.
A) thermal energy
8. A scientist designed a foam container to help keep frozen foods from melting. Which best explains how the foam works?
D) It reduces the amount of thermal energy that is transferred from the inside to the outside of the container.
9. The diagram shows movement of thermal energy. In which areas of the diagram does conduction occur? (look at the screenshot)
B) X and Z
10. Nuclear reactions in a reactor produce a lot of thermal energy. That energy then flows and warms up water, which boils and produces steam. The stream then turns turbines that generate electricity. Which statement below can be made about the production of electricity in a nuclear reactor?
B) Heat flows from the reactor to the water.
11. A stovetop burner on medium reaches 200° C. Which other objects will heat from the burner flow to?
Any answer you choose is correct on Connexus (look at the screenshot)
12. Heat transfer between two substances is affected by specific heat and the
D) amount of time and area of physical contact between the substances.
13. Which of these results in kinetic energy of an object?
B) motion
14. Carmen is heating some water and trying to measure the temperature of water using a Celsius thermometer. Which measurement can she expect once the water begins to boil?
B) 100° C
15. Which shows the formula for converting from degrees to Celsius to degrees Fahrenheit?
A) °F = (9/5 × °C) + 32
16. Which of these indicates that a liquid has transferred thermal energy to the air?
D) The liquid decreases in temperature, and its particles lose kinetic energy.
I took the test ALL of these answers are 100% correct on Connexus (they should be the same for everyone tho)
You're welcome and hope this helps!! :)
Identify the energy levels from which the 410.2 nm emission line of the Balmer series of the
hydrogen atom originates, i.e., state the values of ninitial and nfinal. What is the frequency of the
radiation involved in the transition between these levels?
The energy level from which is emitted is n = 6
The frequency is\(7.3 * 10^14\) Hz
What is the energy level?The Rydberg equation is a mathematical formula that relates the wavelengths of light emitted by an atom to the energy levels of its electrons.
Using the Rydberg equation;
1/λ= RH (1/\(n_{2}^2\) - 1/\(n_{1} ^2\))
1/\(410.2 * 10^-9\) = \(1.097 * 10^7\)(1/\(2^2\) - 1/ /\(n_{1} ^2\))
1/\(4.102 * 10^-7\) = \(1.097 * 10^7\)(1/4 - 1/\(n_{1} ^2\))
1/\(4.102 * 10^-7\) * 1/ \(1.097 * 10^7\) = (1/4 - 1/\(n_{1} ^2\))
0.22 = 0.25 - 1/\(n_{1} ^2\)
0.22 - 0.25 = - 1/\(n_{1} ^2\)
-0.03 = - 1//\(n_{1} ^2\)
\(n_{1}\) = 6
Using;
f = c/λ
\(3 * 10^8/4.102 * 10^-7 \\f = 7.3 * 10^14 Hz\)
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A roller coaster is at a peak of 20m and has a mass of 900kg. What is the potential energy of the roller coaster?
O 100000 J
10000 J
O 9.8 J
O 176400 J
The potential energy of the roller coaster is 176,400 J (joules).
The potential energy of an object is given by the formula PE = mgh, where PE is the potential energy, m is the mass of the object, g is the acceleration due to gravity, and h is the height or vertical position of the object.
In this case, the roller coaster is at a peak of 20m and has a mass of 900kg. The acceleration due to gravity, g, is approximately 9.8 \(m/s^2\).
Using the formula, we can calculate the potential energy:
PE = mgh
= (900 kg)(9.8 \(m/s^2\))(20 m)
= 176,400 J
Therefore, the potential energy of the roller coaster is 176,400 J (joules).
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When is it more helpful to look at the whole distributions with histograms?
Histograms are graphs that display the distribution of your continuous data. ... measurements and want to understand the distribution of values and look for ... Download the CSV data file to make most of the histograms in this blog post: Histograms. In the field of statistics, we often use summary statistics to describe an entire ...
Blood is 92% water. Blood is
drawn using a capillary tube.
Write 1 sentence explaining how it
illustrates this characteristic of
water. Use the terms adhesion
and capillary action.
Answer:
Plasma, which constitutes 55% of blood fluid, is mostly water (92% by volume), and contains proteins, glucose, mineral ions, hormones, carbon dioxide (plasma being the main medium for excretory product transportation), and blood cells themselves.
Explanation:
Capillary motion is crucial for circulating water. Your body's cells would not hydrate without this flow, and crucial communication between your brain and body would slack off, hence blood contains water 92% water helps in capillary action.
What is Capillary action?Capillary action, also known as capillary effect or motion, is the process by which liquid moves through constricted areas without the aid of external forces like gravity but rather with the help of intermolecular forces that exist between the liquid and solid surface (s).
Adhesion: The attraction of two different molecules, such as the hydrogen and oxygen molecules found in water and plastic drinking straws.
Proteins, glucose, mineral ions, hormones, carbon dioxide (plasma is the principal medium for excretory product transfer), and blood cells themselves are contained in plasma, which makes up 55% of blood fluid. Plasma is mostly water (92% by volume) and contains water as well as several other substances.
Therefore, the water contains in the blood helps in capillary action.
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a star with 4 times the sun's mass is about 100 times more luminous than the sun. its main sequence lifetime is
For a star with 4 times the sun's mass is about 100 times more luminous than the sun the main sequence lifetime is 25 times shorter than the Sun's.
What is the sequence lifetime of a star?The sequence lifetime of a star refers to the lifespan of a star celestial body which can be estimated by analyzing the amount of light and mass, in this case, it is equal to 100 / 4 = 25 times shorter than the Sun's.
Therefore, with this data, we can see that the sequence lifetime of a star depends on its light and mass.
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Two moles of an ideal gas at 3.0 atm and 10 °C are heated up to
150 °C. If the volume is held constant during this heating, what
is the final pressure?
Answer:
Explanation:
Two moles of an ideal gas at 3.0 atm and 10°C are heated up to 150 °C. If the volume is held constant during this heating, what is the final pressure? a. 4.5 atm.
If the process is an isochoric process. Then the final temperature of the system will be 4.48 atm.
What is an isochoric process?In the isochoric process, the volume of the system remains the same. A thermodynamics process in which the closed loop system being transformed maintains its same volume.
The pressure is directly proportional to the temperature.
P ∝ T
P = kT
Two moles of an ideal gas at 3.0 atm and 10 °C are heated up to 150 °C. If the process is an isochoric process of heating, then the final temperature of the system will be given as,
P₁ / P₂ = T₁ / T₂
Where P₁ is the initial pressure, P₂ is the final pressure, T₁ is the initial temperature, and T₂ is the final temperature.
Convert the temperature into kelvin.
10 °C = 273.15 + 10 = 283.15 K
150 °C = 273.15 + 150 = 423.15 K
Then the final temperature will be
P₁ / P₂ = T₁ / T₂
3 / P₂ = 283.15 / 423.15
P₂ = 4.48 atm
Thus, the final temperature of the system will be 4.48 atm.
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i need help question 10
please help answering A,B,C in screenshots thank you!
The slope of the graph is 0.5 m/s² and when t = 1.5 s, the predicted displacement (d) of the object is 0.75 meters.
To plot the velocity vs. time graph, we'll use the given data points:
Duration, At (s): 2.0, 4.0, 6.0, 8.0, 10.0, 12.0
Velocity, v (m/s): 6.0, 7.0, 8.0, 9.0, 10.0, 11.0
Let's plot these points on a graph:
Time (s) [x-axis] | Velocity (m/s) [y-axis]
--------------------------------------------
2.0 | 6.0
4.0 | 7.0
6.0 | 8.0
8.0 | 9.0
10.0 | 10.0
12.0 | 11.0
After plotting the points, we can connect them with a straight line to represent the motion of the object. This line represents the velocity vs. time relationship.
Now, let's calculate the slope of this line. The slope of a line represents the rate of change of the dependent variable (velocity) with respect to the independent variable (time). In this case, it gives us the acceleration of the object.
Using the formula for calculating the slope of a line:
Slope (k) = (Change in velocity) / (Change in time)
For the first two points:
Change in velocity = 7.0 - 6.0 = 1.0 m/s
Change in time = 4.0 - 2.0 = 2.0 s
Slope (k) = 1.0 m/s / 2.0 s = 0.5 m/s²
Therefore, the slope of the graph is 0.5 m/s².
Now, to answer part B, the physical significance of the slope value is that it represents the object's acceleration. In this case, the constant acceleration experienced by the object is 0.5 m/s².
Moving on to part C, we are given the equation d = kt, where d represents the displacement and t represents time. Since the object is experiencing constant acceleration, the equation can be rewritten as d = 0.5t, where 0.5 is the acceleration (k).
To predict the value of "d" when t = 1.5 s, we can substitute the value of t into the equation:
d = 0.5 * 1.5 = 0.75 meters
Therefore, when t = 1.5 s, the predicted displacement (d) of the object is 0.75 meters.
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The probable question may be:
An object is subjected to a constant acceleration along a frictionless track. A student measures its velocity (v) after specific durations (At). The student uses a graph to analyze the truck's motion.
Duration, At, (s) :- 2.0,4.0,6.0,8.0,10.0,12.0.
Velocity, v, (m/s) :- 6.0,7.0,8.0,9.0,10.0,11.0
A. Plot the velocity (in meters/sec) vs. time (seconds). The velocity is the y-axis and time is the x-axis. Use any graphing software you like or graph this data in pencil on graph paper. Excel has a nice graphing package. Calculate the slope of this graph. You will
B. What is the physical significance of the slope value computed in part A?
C. Having determined the slope of the line, you can now write d = kt. Use this equation to predict a value of "d" when t = 1.5 s.
HELP When the forces are applied in the same direction, how do you determine net force?
Answer:
Explanation:
If two forces act on an object in the same direction, the net force is equal to the sum of the two forces.
The binding energy of a nucleus is always negative.Question 4 options:TrueFalse
ANSWER
False.
EXPLANATION
Nuclear binding energy is the energy that is required to split the nucleus (of an atom) into nucleons: protons and neutrons.
The binding energy of a nucleus is always positive because nuclei require energy to separate them and it is impossible for nuclei to gain energy by being separated.
Therefore, the answer is false.
Kelly lifts a 4500-newton barbell at a height of 7 meters. What are the joules of work being put out?
Pls help and fast <3
Answer:
31,500 joules
Explanation:
Work = force * distance * cos(theta)
Force = 4500N (weight of the barbell)
Distance = 7m (the height lifted)
Theta = 0 (cosine of 0 degrees is 1, since the force and distance are in the same direction)
So, Work = 4500 N * 7m * cos(0)
Work = 31,500 joules
What is the momentum of an 8 kg bowling ball rolling at 2 m/s straight to the pins?
The momentum of an 8 kg bowling ball rolling at 2 m/s straight to the pins is 16 kg m/s.
What is momentum?As momentum depends on both velocity and the direction of the body's motion, it is quantified by "mass velocity". Since velocity is a vector and mass is a scalar, momentum is a vector quantity. It is given by the formula:
p = mv
p = 8 × 2
p = 16 kg m/s
What is velocity?Velocity can be defined as the rate at which something moves in a specific direction. as the speed of a car driving north on a highway or the pace at which a rocket takes off. Because the velocity vector is scalar, its absolute value magnitude will always equal the motion's speed.
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What is the magnetic force on a 2.0-m length of (straight) wire carrying a current of 30 A in a region where a uniform magnetic field has a magnitude of 55 mT and is directed at an angle of 20° away from the wire?
To determine the magnetic force on a straight wire carrying a current in a uniform magnetic field, we can use the formula for the magnetic force:
F = I * L * B * sin(θ)
where:
F is the magnetic force,
I is the current in the wire,
L is the length of the wire,
B is the magnitude of the magnetic field, and
θ is the angle between the wire and the magnetic field.
In this case, the values are:
I = 30 A (current in the wire)
L = 2.0 m (length of the wire)
B = 55 mT = 0.055 T (magnitude of the magnetic field)
θ = 20° (angle between the wire and the magnetic field)
Substituting the values into the formula:
F = 30 A * 2.0 m * 0.055 T * sin(20°)
Calculating sin(20°):
F = 30 A * 2.0 m * 0.055 T * 0.3420
F ≈ 1.5714 N
Therefore, the magnetic force on the 2.0-meter length of wire carrying a current of 30 A in a region with a uniform magnetic field of magnitude 55 mT and at an angle of 20° away from the wire is approximately 1.5714 N.
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True or false, wrrect the false
statement:
• The magnetic field created by a flat coil is
uniform.
• Inside a solenoid, the lines of field are
oriented from the north face to the south
face.
• The magnetic field outside Helmholtz
coils is uniform.
• Le champ B à l'intérieur d'un solénoïde
est uniforme.
• The magnitude of B, created by a flat coil
of radius R, at any point in its plane is
B= 2m x 10-NI
R
• The designation of the faces of a wil
depend the sense of the current
traversing it.
Answer:
false
Explanation:
if a 0.08kg cell phone falls of a table at 15 m/s then what is its kinetic energy right before it hits the ground?
The Kinetic energy of the cell phone of mass 0.08 kg is 9 J.
What is kinetic energy?Kinetic energy is the energy of a body in motion.
To calculate the kinetic energy of the cell phone, we use the formula below.
Formula:
K.E = mv²/2............. Equation 1Where:
K.E = Kinetic energy of the cell phonem = Mass of the cell phonev = Velocity of the cell phoneFrom the question,
Given:
m = 0.08 kgv = 15 m/sSubstitute these values into equation 1
K.E = 0.08×15²/2K.E = 9 JHence, the Kinetic energy of the cell phone is 9 J.
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The thermometer bulb should have____
a) high heat capacity
b) No heat capacity
c) Small heat capacity
d) Varying heat capacity
Need help please answer
Answer:
8 + 6 = 14 miles north
Explanation:
A truck is pushed with an acceleration of 1.5 m/s^2. If the mass of the
truck decreases by a factor of 4, what is the new acceleration on the
truck? *
Answer:
6 m/s²
Explanation:
The following data were obtained from the question:
Initial mass (m1) = m
Initial acceleration (a1) = 1.5 m/s²
Final mass (m2) = decreases by a factor of 4 of the initial mass = m/4
Final acceleration (a2) =..?
Finally, we shall determine final acceleration of truck as follow:
Force (F) = mass (m) × acceleration (a)
F = ma
F = m1 × a1 = m2 × a2
m1 × a1 = m2 × a2
m × 1.5 = m/4 × a2
m × 1.5 = m × a2 /4
Cross multiply
m × 1. 5 × 4 = m × a2
m × 6 = m × a2
6m = m × a2
Divide both side by m
a2 = 6m/m
a2 = 6 m/s²
Thus, the new acceleration of the truck is 6 m/s²
The nose is relation to the foot
RLLY?
Explanation:
ALSO
MY DAD ALWAYS TELLS ME THAT IF YOUR FEET ARE COLD THAT YOU NEED TO PUT A HAT ON?!?!?!?!?!
A solid cylinder of uniform density of 0.85 g/cm3 floats in a glass of water tinted light blue by food coloring.
Its circular surfaces are horizontal. What effect will the following changes, each made to the initial system, have on X, the height of the upper surface above the water? The liquids added do not mix with the water, and the cylinder never hits the bottom.
1. The cylinder is replaced with one that has the same density and diameter, but with half the height.
2. Some of the water is removed from the glass.
3. A liquid with a density of 1.06 g/cm3 is poured into the glass.
4. The cylinder is replaced with one that has the same height and diameter, but with density of 0.83 g/cm3.
5. A liquid with a density of 0.76 g/cm3 is poured into the glass.
6. The cylinder is replaced with one that has the same density and height, but 1.5× the diameter.
Options are: Increase, Decrease, No change
The buoyant force acting on the cylinder is, \(Fb = \rho Ahg\). Here A is the cross-sectional area of the cylinder, h is the height of the cylinder, ρ is the density of the cylinder, and g is the acceleration due to gravity.
This buoyant force is also equal to the volume of the fluid displaced. \(Fb = \sigma h(A-x)g\). Here σ is the density of the fluid.
Equate the above two equations and solve for x.
\(\rho Ahg = \sigma A(h-x)g\\\rho h = \sigma h - \sigma x\\x = \frac{(\sigma - \rho)h}{\sigma}\)
So, the distance x depends on the density of the fluid, density of the cylinder and the height of the cylinder.
1. The density of the cylinder is same and distance x is independent of the diameter of the cylinder. Therefor, there will be no change in the distance x. Hence, the correct answer is No change.
2. Now the height is changing keeping the density same. As the distance x is directly proportional to the height, the distance x will increase.
3. The density of the added liquid is greater than of the water and it does not mix with the water. So, the liquid will settle down and there will be no change in the distance x.
4. The density of the added liquid is less than that of the water and it does not mix with the water. So, the liquid will not settle down and the distance x will change. The change in distance x can be determined as follow:
\(\rho Agh = \sigma' Axg + \sigma A(h-x)g\\\rho h=\sigma' x + \sigma h - \sigma x\\x=(\frac{\sigma - \rho}{\sigma - \sigma'})h\)
Here, σ' is the density of the added liquid.
From the above relation it is clear, that on adding the liquid of the density less than that of water, the denominator term become small ando so the value of x will increase.
5. On removing some of the water inside the glass, the height of the water column will decrease, but the value of x does not depend on the height of the water column. So, there will be no change in the distance x.
6. The density of the new cylinder is smaller than that of the earlier one. So, the numerator term will increase. Therefore, the value of x will increase.
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Which statement describes friction?
Answer:
include the statements pls so i can choose wich one it is and tell you
Explanation:
6.
What happens at the condensation point?
Answer:
Condensation point is when the temperature at which a vapor condenses into a liquid without a change in the temperature of the substance.
A 4.80-kg block is at rest on a horizontal floor. If you push horizontally on the 4.80-kg block with a force of 12.0 N, it just starts to move.What is the coefficient of static friction?
The given problem can be exemplified using the following free-body diagram:
In the diagram we have:
\(\begin{gathered} N=\text{ normal force} \\ m=\text{ mass} \\ g=\text{ acceleration of gravity} \\ F=\text{ pushing force} \\ F_f=\text{ friction force} \end{gathered}\)Now, we are asked to determine the coefficient of static friction. To do that we will add the forces in the horizontal direction. We will take the forces to the left as positive, we get:
\(\Sigma F_h=F-F_f\)Now, since we are considering the moment that the object will begin its movement we will use an acceleration of zero, therefore, the sum of forces is equal to zero:
\(F-F_f=0\)Now, To determine the value of the force of friction we will use the following relationship:
\(F_f=\mu_sN\)Where:
\(\mu_s=\text{ coefficient of static friction}\)Now, we determine the normal force by adding the forces in the vertical direction, we get:
\(\Sigma F_v=N-mg\)Since there is no movement in this direction the sum of forces must be equal to zero:
\(N-mg=0\)Now we solve for the normal force by adding "mg" to both sides:
\(N=mg\)Now we substitute this value in the formula for friction:
\(F_f=\mu_smg\)Now we substitute in the sum of horizontal forces:
\(F-\mu_smg=0\)Now we will solve for the coefficient of static friction, to do that we will add the relationship for the friction on both sides:
\(F=\mu_smg\)Now we divide both sides by "mg":
\(\frac{F}{mg}=\mu_s\)Now we substitute the values:
\(\frac{12N}{(4.8\operatorname{kg})(9.8\frac{m}{s^2})}=\mu_s\)Solving the operations we get:
\(0.26=\mu_s\)Therefore, the coefficient of static friction is 0.26.
A car starts from rest and accelerates at a constant rate in a straight line. In the first second the car moves a distance of 2.0 meters. How much additional distance will the car move during the second second of its motion?
Since the car is accelerating at a constant rate, the distance it travels during each second of its motion will be directly proportional to the time it has been accelerating.
In the first second, the car moved a distance of 2 meters, and in the second second, it will move twice the distance of the first second, so the car will move additional distance of 2*2 = 4 meters during the second second of its motion.
The distance traveled during the second second of its motion is 1/2 * 2 = 1 meters.
A car that accelerates at a constant rate will move a distance equal to the initial velocity multiplied by time plus 1/2 the acceleration multiplied by the square of time. Since the car starts from rest, the initial velocity is zero.
Therefore, the distance traveled during the second second is 1/2 * acceleration \(* (time)^2 = 1/2 * a * t^2 = 1/2 * a * 1^2 = 1/2 * a\) Since the car moved 2.0 meters in the first second, it means the acceleration is\(2m/s^2\), and the distance traveled during the second second is 1/2 * 2 = 1 meters.
Learn more about initial velocity:
https://brainly.com/question/9365999
Work is NOT done by a person when she?
pulls a sled across the ice covered backyard
lifts a book up off a desk
pushes on a desk to move it 3 m forward
pushes on a building
Answer:
I think it is pulling the sled off the ice covered back yard.