Answer:
yes I think it is possible
Two equal and opposite charges are placed 40mm apart,if the force between them is found to be 0.5N Calculate the magnitude of the charge
True False: Marke each statement as true or false.
shift
1. Light intensity affects the rate of photosynthesis.
in
2. Energy is required by all organisms for life.
3. The ability of a plant to repair tissue depends on respiration.
4. The gas needed for photosynthesis is carbon dioxide (CO2).
5. Plants only carry on photosynthesis, not respiration.
6. Respiration can occur without photosynthesis.
Answer:
1) true 2) true 3) true 4) true 5) false 6) false
Explanation:
the density of gold is 19g/m³ what is the volume of 38g
let the volume be x
19 = 38/x
x=38/19
x=2
volume is 2 cm^3
A cloth hat and large rock are dropped at at the same time on the moon
Answer:
What’s the question??
Explanation:
A cubic box is completely filled with 2800 g of water. What is the length of one side of the box, in meters?
m
Explain your reasoning.
Since the density of water is
cm3 is
g/cm3, then the volume of 2800 g of water is
cm on each side. Converting [ cm to meters, the cube is
Proy
13 of 15
⠀⠀⠀
Next
cm³. A cubic box with a volume of [
m on each side.
The density of water is approximately 1 g/cm^3. Therefore, the volume of 2800 g of water would be 2800 cm^3 because density is mass/volume, and so volume is mass/density.
Since this volume is inside a cubic box, the length of each side of the cube (a, for instance) could be found by taking the cubic root of the volume. This is because the volume of a cube is calculated by a^3 (length of one side cubed). Hence, a = cube root of 2800 cm^3 ≈ 14.1 cm.
Converting centimeters to meters (as 1 meter is equal to 100 centimeters), we get approximately 0.141 meters.
So the filled cubic box has a side length of approximately 0.141 m.
3. An object with a mass of 3.2 kg has a force of 6.2 N applied to it. What is the resulting acceleration
of the object?
Answer:
The answer is 1.94 m/s²Explanation:
The acceleration of an object given it's mass and the force acting on it can be found by using the formula
\(a = \frac{f}{m} \\ \)
where
f is the force
m is the acceleration
From the question we have
\(a = \frac{6.2}{3.2} \\ = 1.9375\)
We have the final answer as
1.94 m/s²Hope this helps you
can you please help i cant seem to find the answer The diameter of the right side d_1 is 2 cmThe diameter of the left side d_2 is 8 cm
Given data:
* The speed of the water coming out of the pipe is,
\(v_1=14.9\text{ m/s}\)* The diameter of the left side of pipe is,
\(d_2=8\text{ cm}\)* The diameter of the right side of the pipe is,
\(d_1=2\text{ cm}\)Solution:
(a). The area of the right side of pipe is,
\(A_1=\pi r^2_1\)The radius of the right side of pipe is,
\(\begin{gathered} r_1=\frac{d_1}{2} \\ r_1=\frac{2}{2} \\ r_1=1\text{ cm} \end{gathered}\)Thus, the area of the right side of pipe is,
\(\begin{gathered} A_1=\pi\times(1\times10^{-2})^2 \\ A_1=\pi\times(0.01)^2 \\ A_1=0.000314m^2 \end{gathered}\)The volume of the water coming out from the right side of the pipe is,
\(V=v_1t\times A_1\)Where t is the time taken, v_1 is the velocity of the water, and A_1 is the area of right side of pipe,
Substituting the known values,
\(\begin{gathered} V=14.9\times7\times60\times0.000314 \\ V=1.97m^3 \end{gathered}\)Thus, the volume of water flows into the atmosphere is 1.97 meter cube.
When is an object positively charged?
Answer:
when it has a fewer amount of electrons than protons
An 75-kilogram skier slides on waxed skis along a horizontal surface of snow at constant velocity while pushing with his poles. What is the horizontal component of the force pushing him forward? (1) 0.05 N (2) 40 N (3) 37 N (4) 4 N
[Use: Ff = µ Fn; remember Fn = Fg = mg]
The horizontal component of the force pushing him forward is 37 N.
What is force?A force is an effect that can alter an object's motion according to physics. An object with mass can change its velocity, or accelerate, as a result of a force. An obvious way to describe force is as a push or a pull. A force is a vector quantity since it has both magnitude and direction.
Frictional force due to ice, F = μN
Normal force N = mg = 75*9.8 = 735 N
Frictional force = 0.05*735 = 36.75 N
Coefficient of friction, μ for ice is 0.05
The horizontal component of the force pushing him forward is 37 N.
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Mary pushed a box across the floor with 54N to the left and Doug helped her by exerting a force
of 75N to the left and another force of 20N was exerted on the box in the opposite direction,
what is the net force acting on the box? *
Help plzz
The triceps muscle in the back of the upper arm is primarily used to extend the forearm. Suppose this muscle in a professional boxer exerts a force of 1.95 × 103 N with an effective perpendicular lever arm of 3.1 cm, producing an angular acceleration of the forearm of 125 rad/s2. What is the moment of inertia of the boxer's forearm?
Answer:
I = 0.483 kgm^2
Explanation:
To know what is the moment of inertia I of the boxer's forearm you use the following formula:
\(\tau=I\alpha\) (1)
τ: torque exerted by the forearm
I: moment of inertia
α: angular acceleration = 125 rad/s^2
You calculate the torque by using the information about the force (1.95*10^3 N) and the lever arm (3.1 cm = 0.031m)
\(\tau=Fr=(1.95*10^3N)(0.031m)=60.45J\)
Next, you replace this value of τ in the equation (1) and solve for I:
\(I=\frac{\tau}{\alpha}=\frac{60.45Kgm^2/s ^2}{125rad/s^2}=0.483 kgm^2\)
hence, the moment of inertia of the forearm is 0.483 kgm^2
A atom in its ground state contains 18 electrons. how many of these electrons are in orbital l=0 values?
How much is 813 in grams
I Math
To convert 813 into grams if it is already in grams, then the value remains as 813 grams. If it is in pounds, 813 pounds would be approximately 368,646.696 grams. If it is in kilograms, 813 kilograms would be equal to 813,000 grams.
To convert 813 into grams, we need to know the unit of measurement you're referring to. Grams are typically used to measure the weight of objects, but without additional context, it's difficult to provide an accurate answer.
If you are referring to 813 grams, then the conversion is straightforward, as it is already in grams.
If you are referring to another unit, such as pounds or kilograms, we can convert it to grams:
If you meant 813 pounds, one pound is approximately equal to 453.592 grams. Therefore, 813 pounds would be approximately 368,646.696 grams.
If you meant 813 kilograms, one kilogram is equal to 1,000 grams. Therefore, 813 kilograms would be equal to 813,000 grams.
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A team of horses is pulling a 910 kg wagon with a force of 4500 N. Assuming there are no other forces on the wagon, what is the wagon's acceleration?
1. A Ograph A Ograph B Ograph c Which graph represents what happens to the pressure in a tire as air is added to the tire, assuming the temperature is constant?
Answer:
Explanation:
It's graph A because the pressure in the tire is increasing as the amount of air going into it increases. B says the pressure drops exponentially as air goes in, and C says that the pressure stays the same as air goes in. Pressure in a tire increases proportionally to the amount of air in it.
why are two astronauts in space unable to hear one another
In space, there is no air to carry sound waves. Sound waves are vibrations that travel through a medium, such as air, water, or solid objects. Without a medium to carry the vibrations, sound cannot be transmitted. This is why astronauts in space cannot hear one another or any other sounds. They must use radios or other communication devices to communicate with one another.
Answer:
Below
Explanation:
Unless they have an electronic intercom in their spacesuits. there is no air between them to conduct the soundwaves.
An increase in voltage results in
If the current is held constant, an increase in voltage will result in an increase in resistance.
hope it helps...!!!
A bus in traffic increases its speed from 10km/hr to 23km/hr in 2 minutes. What is the average acceleration of the bus?
The average acceleration of the bus is −6.00 m/s².
What is average acceleration?The definition of average acceleration is the change in velocity per unit of time. Acceleration is measured in squared time-distance units. The word "average" is interpreted as a symbol with a bar over it, therefore "a-bar" stands for average acceleration. Calculating Average Acceleration: The change in velocity is calculated by dividing the end velocity by the initial velocity, then multiplying the result by the change in time. This result is known as the average acceleration (a). a = v t = v f v I t. How quickly an object is travelling in a specific direction is determined by its velocity. In the formula -a=vt=vfv0tft0, where an is average acceleration, v is velocity, and t is time, the average acceleration is the rate at which velocity changes.a = ? ; Δt = 1.50 s ; v1 = 9.00 m/s ; v2 = 0.00m/s
The formula to use in this case is the definition of acceleration stating that the acceleration a = Δv / Δt or a = (v2- v1) / Δt where v2 is the final velocity and v1 is the initial velocity.
Solving for the acceleration a
a = (v2- v1) / Δt
a = (0 - 9.00 m/s) / 1.50 s
a = - 9.00 m/s / 1.50 s
a = −6.00 m/s^2
The average acceleration of the bus is −6.00 m/s^2.
The complete question is,
When a bus comes to a sudden stop to avoid hitting a dog, it slows from 9.00 m/s to 0.00m/s in 1.50 seconds. What is the average acceleration of the bus?
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Please provide an explanation.
Thank you!!
Answer:
(a) 22 kN
(b) 36 kN, 29 kN
(c) left will decrease, right will increase
(d) 43 kN
Explanation:
(a) When the truck is off the bridge, there are 3 forces on the bridge.
Reaction force F₁ pushing up at the first support,
reaction force F₂ pushing up at the second support,
and weight force Mg pulling down at the middle of the bridge.
Sum the torques about the second support. (Remember that the magnitude of torque is force times the perpendicular distance. Take counterclockwise to be positive.)
∑τ = Iα
(Mg) (0.3 L) − F₁ (0.6 L) = 0
F₁ (0.6 L) = (Mg) (0.3 L)
F₁ = ½ Mg
F₁ = ½ (44.0 kN)
F₁ = 22.0 kN
(b) This time, we have the added force of the truck's weight.
Using the same logic as part (a), we sum the torques about the second support:
∑τ = Iα
(Mg) (0.3 L) + (mg) (0.4 L) − F₁ (0.6 L) = 0
F₁ (0.6 L) = (Mg) (0.3 L) + (mg) (0.4 L)
F₁ = ½ Mg + ⅔ mg
F₁ = ½ (44.0 kN) + ⅔ (21.0 kN)
F₁ = 36.0 kN
Now sum the torques about the first support:
∑τ = Iα
-(Mg) (0.3 L) − (mg) (0.2 L) + F₂ (0.6 L) = 0
F₂ (0.6 L) = (Mg) (0.3 L) + (mg) (0.2 L)
F₂ = ½ Mg + ⅓ mg
F₂ = ½ (44.0 kN) + ⅓ (21.0 kN)
F₂ = 29.0 kN
Alternatively, sum the forces in the y direction.
∑F = ma
F₁ + F₂ − Mg − mg = 0
F₂ = Mg + mg − F₁
F₂ = 44.0 kN + 21.0 kN − 36.0 kN
F₂ = 29.0 kN
(c) If we say x is the distance between the truck and the first support, then using our equations from part (b):
F₁ (0.6 L) = (Mg) (0.3 L) + (mg) (0.6 L − x)
F₂ (0.6 L) = (Mg) (0.3 L) + (mg) (x)
As x increases, F₁ decreases and F₂ increases.
(d) Using our equation from part (c), when x = 0.6 L, F₂ is:
F₂ (0.6 L) = (Mg) (0.3 L) + (mg) (0.6 L)
F₂ = ½ Mg + mg
F₂ = ½ (44.0 kN) + 21.0 kN
F₂ = 43.0 kN
Answer:
a. Left support = Right support = 22 kNb. Left support = 36 kN Right support = 29 kNc. Left support force will decrease Right support force will increase.d. Right support = 43 kNExplanation:
given:
weight of bridge = 44 kN
weight of truck = 21 kN
a) truck is off the bridge
since the bridge is symmetrical, left support is equal to right support.
Left support = Right support = 44/2
Left support = Right support = 22 kN
b) truck is positioned as shown.
to get the reaction at left support, take moment from right support = 0
∑M at Right support = 0
Left support (0.6) - weight of bridge (0.3) - weight of truck (0.4) = 0
Left support = 44 (0.3) + 21 (0.4)
0.6
Left support = 36 kN
Right support = weight of bridge + weight of truck - Left support
Right support = 44 + 21 - 36
Right support = 29 kN
c)
as the truck continues to drive to the right, Left support will decrease
as the truck get closer to the right support, Right support will increase.
d) truck is directly under the right support, find reaction at Right support?
∑M at Left support = 0
Right support (0.6) - weight of bridge (0.3) - weight of truck (0.6) = 0
Right support = 44 (0.3) + 21 (0.6)
0.6
Right support = 43 kN
PLEASE ANSWER FASG I WILL MARK BRAINELIST PLEASEEEEE
The number of protons in the nucleus of an atom determines the species of the atom, i.e., the element to which the atom belongs. An atom has the same number of protons and neutrons. But the electron number cannot be used instead because (5 points)
a. electrons are not within the nucleus
b. electrons are negatively charged
c. electrons can be removed from or added to an atom
d. electrons are lighter than protons
The electron number cannot be used instead because electrons can be removed from or added to an atom (option C)
Why the electron number cannot be used instead?The element of an atom is determined by its proton count, while the electron count can exhibit variability. Take, for instance, a sodium atom, which encompasses 11 protons and 11 electrons. However, it has the capacity to relinquish one electron, transforming into a sodium ion housing only 10 electrons.
This occurs due to the relatively loose binding of electrons to the nucleus, enabling their removal through the influence of an electric field or alternative mechanisms.
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Select the correct answer.
A boat moves 60 kilometers east from point A to point B. There, it reverses direction and travels another 45 kilometers toward point A. What are the total
distance and total displacement of the boat?
O A.
OB.
O C.
O D.
The total distance is 105 kilometers and the total displacement is 45 kilometers east.
The total distance is 60 kilometers and the total displacement is 60 kilometers east.
The total distance is 105 kilometers and the total displacement is 15 kilometers east.
The total distance is 60 kilometers and the total displacement is 45 kilometers east.
The total distance is 105 kilometers and the total displacement is 15 kilometers east. Option C
How to solve for the total distanceTo calculate the total distance, we add the distances traveled in each leg of the journey: 60 kilometers (from A to B) + 45 kilometers (from B back to A) = 105 kilometers.
However, displacement refers to the change in position of an object in a straight line from its starting point to its ending point. In this case, since the boat starts and ends at the same point (A), the total displacement is zero.
Hence The total distance is 105 kilometers and the total displacement is 15 kilometers east.
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Three balls, of mass m, 5m, and 3m, are at the vertices of an equilateral triangle with side lengths equal to L. What is the magnitude of the force on mass m from the two other masses, in terms of G, m, and L
Answer:
F_{total}= 8.25 \(\frac{G m^2}{L^2}\), θ’= 194º
Explanation:
To solve this problem we must use the law of universal gravitation and vectorly add the forces
F = \(G \frac{m_{1} m_{2} }{r^{2} }\)
Let us call the mass m with the subscript 1, the mass 3m with the subscript 3 and the mass 5m with the subscript 5, the total force on particle 1 is
F_total = F₁₅ + F₁₃
The bold are vectors, in the attachment we can see a diagram of the angles and the forces, the distance between the masses is
r = L
let's find the force between m1 and m5
F₁₅ = G m₁ m₅ / r²
F₁₅ = G m 5m / L²
F₁₅ = G 5m² / L²
this force is on the line that joins the two masses, let's use trigonometry to decompose this force
cos 30 = F₁₅ₓ / F₁₅
sin 30 = \(\frac{Fx_{15y} }{F_{15} }\)
F₁₅ₓ = F₁₅ cos 30
\(F_{15y}\) = F₁₅ sin 30
equally with the force between mass 1 and mass 3
F₁₃ = -G 3 m² / L²
F₁₃ₓ = F₁₃ cos 30
F_{13y} = F₁₃ sin 30
to find the total force we can add each component independently, see attached
X axis
F_total x = -F₁₅ₓ + F₁₃ₓ
F_total x = -G 5m2 / L² + G 3m² / L²
F_total x = - G 2m² / L²
Y axis
F_total y = - F_{15y} - F_{13y}
F_total y = - G 5m² / L² - G 3 m² / L²
F_toal y = - G 8 m² / L²
We can give the result in two ways
1) F_total = - G m ^ 2 / L² (2 i ^ + 8 j ^)
2) in the form of module and angle.
Let's use the Pythagorean theorem
\(F_{total}^{2} = F_{total x}^{2} + F_{total y}^2\)
\(F_{total}\) = \(\frac{G m^{2} }{L^2} \sqrt{(2^2 + 8^2)}\)
F_{total}= 8.25 \(\frac{G m^2}{L^2}\)
with trigonometry
tan θ = \(\frac{F_{total y} }{F_{total x} }\)
tan θ = 8/2
θ = tan⁻¹ 4
θ = 76º
if we measure this angle from the positive side of the x axis in a counterclockwise direction
θ’= 270 -76
θ’= 194º
Two particles are at the same point at the same time, moving in the same direction. Par- ticle A has an initial velocity of 7.7 m/s and an acceleration of 1.8 m/s². Particle B has an initial velocity of 2.9 m/s and an acceleration of 5.7 m/s². At what time will B pass A? Answer in units of s.
The particle B will pass particle A in 1.10s.
Equation :Using kinematic formula,
d = Vini x t + 1/2 at²
where,
d is distance
Vini is velocity initial
a is acceleration
t is time
So, putting values
7.7 t + 1/2 x 1.8 t^² = 2.9 t + 1/2 x 5.7 t²
7.7 t + 2.7 t² = 2.9 t + 8.55 t²
t + t² / t + t² = 2.9 + 8.55 / 7.7 + 2.7
t = 1.10s
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A tennis ball is shot straight up with an initial velocity of 34 m/s. What is its velocity two seconds after launch?
Answer:
The speed after 2 seconds is 14.4 m/s
Explanation:
Vertical Launch Upwards
In a vertical launch upwards, an object is launched vertically up from a height H without taking into consideration any kind of friction with the air.
The speed changes from an initial value vo to a final value vf, given by:
\(v_f=v_o-g.t\)
Where g is the gravitational acceleration (\(9.8\ m/s^2\))
The tennis ball is shot up with an initial speed of vo=34 m/s. We are required to find the final speed at t=2 s:
\(v_f=34-9.8*2\)
\(v_f=14.4\ m/s\)
The speed after 2 seconds is 14.4 m/s
the velocity after 2 seconds of launch is 14.4 m/s
the initial velocity(a) is 34m/s
the time(t) is 2 seconds
acceleration(a) due to gravity is 9.8g
the formula is
v= u - at
v= 34 -(9.8)(2)
= 34 - 19.6
= 14.4 m/s
hence the final velocity is 14.4 m/s
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During a circus act, an elderly performer thrills the crowd by catching a cannon ball shot at him. The cannon ball has a mass of 39.0 kg and its horizontal component of velocity is 6.50 m/s just before the 65.0 kg performer catches it. If the performer is initially motionless on nearly frictionless roller skates, what is his speed immediately after catching the cannon ball
Answer:
\(2.4375\ \text{m/s}\)
Explanation:
\(m_1\) = Mass of cannon ball = 39 kg
\(m_2\) = Mass of performer = 65 kg
\(u_1\) = Initial horizontal component of cannon ball's velocity = 6.5 m/s
\(u_2\) = Initial horizontal component of performer's velocity = 0
v = Velocity of combined mass
As the momentum of the system is conserved we have
\(m_1u_1+m_2u_2=(m_1+m_2)v\\\Rightarrow v=\dfrac{m_1u_1+m_2u_2}{m_1+m_2}\\\Rightarrow v=\dfrac{39\times 6.5+0}{39+65}\\\Rightarrow v=2.4375\ \text{m/s}\)
The speed of the performer immediately after catching the cannon ball is \(2.4375\ \text{m/s}\).
0.3050 has
significant figures
?
Answer:
NO
Explanation:
because it just doesn't.
A piece of copper weighing 400g is heated to 100°c and quickly transferred to a copper calorimeter of mass 10g containing 100g of liquid of unknown specific heat capacity at 30°c. If the final temperature of the mixture is 50°c, calculate the specific heat capacity of the liquid. (S.H.C of copper is 390J/kg/k)
A piece of copper at 100°C is transferred to a copper calorimeter with a liquid at 30°C. The final temperature is 50°C. By applying the principle of conservation of energy, the specific heat capacity of the liquid is calculated to be approximately 2100 J/kg/°C.
To calculate the specific heat capacity of the liquid, we can apply the principle of conservation of energy. The heat lost by the copper piece will be equal to the heat gained by the liquid and calorimeter.
The heat lost by the copper piece can be calculated using the formula:
Heat lost = Mass of copper × Specific heat capacity of copper × Temperature change
Given:
Mass of copper = 400 g
Specific heat capacity of copper = 390 J/kg/°C (assuming it remains constant)
Temperature change of copper = 100°C - 50°C = 50°C
Heat lost = 400 g × 390 J/kg/°C × 50°C
Heat lost = 7,800,000 J
The heat gained by the liquid and calorimeter can be calculated using the formula:
Heat gained = (Mass of liquid + Mass of calorimeter) × Specific heat capacity of liquid × Temperature change
Given:
Mass of liquid = 100 g
Mass of calorimeter = 10 g
Temperature change of liquid = 50°C - 30°C = 20°C
Heat gained = (100 g + 10 g) × Specific heat capacity of liquid × 20°C
Now, by equating the heat lost and heat gained:
7,800,000 J = (110 g) × Specific heat capacity of liquid × 20°C
Specific heat capacity of liquid = 7,800,000 J / (110 g × 20°C)
Specific heat capacity of liquid ≈ 3545.45 J/kg/°C
Therefore, the specific heat capacity of the liquid is approximately 3545.45 J/kg/°C.
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20 POINTS NEED ANSWER ASAP Is this a scientific model? Use complete sentences to explain why or why not.
A map showing the winter outlook for the United States
Public Domain
umm actually is 10 points
What is the difference between classical mechanics and quantum mechanics?
Classical mechanics describes the motion of objects on a macroscopic scale, while quantum mechanics deals with the behavior of particles on a microscopic scale. Classical mechanics is deterministic, meaning that it predicts precise outcomes based on initial conditions, while quantum mechanics is probabilistic, providing probabilities of different outcomes. Classical mechanics follows the principle of causality, where every effect has a specific cause, whereas quantum mechanics introduces inherent uncertainty and wave-particle duality. Classical mechanics is well-suited for describing everyday objects, while quantum mechanics is necessary to explain the behavior of particles at the atomic and subatomic levels.
~~~Harsha~~~
A lift with the total mass of 2200 kg was elevated by an electric motor from the initial level at 4m to 80m above the floor of the shaft. Steel cables holding the lift broke when the lift reached the 80m level. A linear amortisation spring of uncompressed ("relaxed") length equal to 4m is installed at the floor of the shaft. Neglect friction.
Calculate:
(a) the work done by the electric motor to elevate the lift from the level at 4m to the level at 80m,
(b) the velocity of the free falling lift at the moment of contact with the spring (at the level of 4m),
(c) the minimum stiffness of the spring (see the last part of question (d)),
(d) the total energy of the lift–spring system
• at the initial state of the lift at the level of 4m,
• at the 80m level of the lift,
• at the moment of contact of the lift with the spring during the fall,
• at the lowest lift level corresponding to the maximum compression of the spring, which is 1m above the shaft floor.
Answer:
a) W = 1,639 10⁶ J, b) v = 38.60 m / s, c) k = 3.78 10⁵ N / m
Explanation:
a) In this part they ask us the work done by the motor, let's use the work energy theorem
W = ΔEm = Em_f - Em₀
W = mh y₂ - mgy₁
W = mg (y₂ -y₁)
W = 2200 9.8 (80 -4)
W = 1,639 10⁶ J
b) for this part let's use conservation of energy
starting point. Highest point
Em₀ = U = m g y₂
final point . Punoit in contact with the spring
Em_f = K + U
Em_f = ½ m v² + m g y₁
Em₀ = Em_f
m g y₂ = ½ m v² + mg y₁
v = √(2g (y₂ - y₁))
v = √(2 9.8 (80-4))
v = 38.60 m / s
c) the stiffness of the spring
starting point. Just when it comes into contact with the spring
Em₀ = K + U
Em₀ = ½ m v² + mgy₁
Final point. With the spring at maximum compression x = 3 m
Em_f = Ke + U
Em_f = ½ k x² + m g y₃
Em₀ = Em_f
½ m v² + mgy₁ = ½ k x² + m g y₃
½ k x² = ½ m v² + m g (y₁ - y₃)
let's calculate
½ 3² k = ½ 2200 38.60² + 2200 9.8 (4 -1)
4.5 k = 1.639 10⁶ +6.468 10⁴ = 1.7036 10⁶
k = 1.7036 10⁶ / 4.5
k = 3.78 10⁵ N / m