Marjan, a skier of mass m, coasts a distance s on level snow to a stop from a speed of v, as depicted in the figure. Use the work-energy principle to find the coefficient of kinetic friction μk between the skis and the snow.
use the relationship wtotal=kfinal−kinitial=δkwtotal=kfinal−kinitial=δk to find the coefficient of kinetic friction between the skis and the snow.

The amount of energy delivered by the heater in a given time interval will be increase by a factor of four

Given:

Current in wire = I

current is double = 2I

To Find:

amount of energy delivered by the heater

Solution:

Scientists define energy as the ability to do work.

The unit of energy is the joule, the unit of power is the watt, and the unit of time is the second.

E = Power x Time = P x T

P = (I)^2 x T

E' = (2I)^2 x T

E' 4I^2T

E' = 4E

So, amount of energy delivered by the heater will be four time initial energy

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The length of a lossless transmission line having a 50-ohm characteristic impedance depends on the frequency of the signal being transmitted.

The length can be calculated using the equation L = λ/4, where L is the length of the transmission line and λ is the wavelength of the signal. The wavelength can be calculated using the equation λ = c/f, where c is the speed of light and f is the frequency of the signal. Therefore, the length of the transmission line can be determined by knowing the frequency of the signal.

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The magnitude of the electrostatic force between two electrons separated by a distance of 1x10^-8 meters is approximately 2.3x10^-28 Newtons.

According to Coulomb's law, the magnitude of the electrostatic force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.

In this case, the charges are both electrons, which have a charge of -1.6x10^-19 Coulombs. Plugging in the values, we get:

F = (kq1q2)/r^2

F = (9x10^9 Nm^2/C^2)(-1.6x10^-19 C)*(-1.6x10^-19 C)/(1x10^-8 m)^2

F ≈ 2.3x10^-28 N

Therefore, the magnitude of the electrostatic force between two electrons separated by a distance of 1x10^-8 meters is approximately 2.3x10^-28 Newtons.

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Answer:

High

Explanation:

Waves with high energy have a higher frequency.

The potential across the capacitor at t = 1.0 seconds, 5.0 seconds, 20.0 seconds respectively is mathematically given as

Question Parameters:

A 1. 0 μf capacitor is being charged by a 9. 0 v battery through a 10 mω resistor.

at

Generally, the equation for the Voltage is mathematically given as

v(t)=Vmax=(i-e^{-t/t})

Therefore

For t=1

V=5(i-e^{-1/10})

t=0.476v

For t=5s

V2=5(i-e^{-5/10})

t=1.967

For t=20s

V2=5(i-e^{-20/10})

V2=4.323v

Therefore, the values of voltages at the various times are

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Complete Question

A 1.0 μF capacitor is being charged by a 5.0 V battery through a 10 MΩ resistor.

Determine the potential across the capacitor when t = 1.0 seconds, 5.0 seconds, 20.0 seconds.

Answer:

c

Explanation:

Answer:

The correct option is;

B. Subtract vectors A from C; \(F_{Net}\) = 12 N

Explanation:

The given parameters are;

The weight of the dresser = 250 N

The force applied by the man = 20 N = C

The frictional force provided by the carpet = 8 N = The component of the weight resisting motion = A

Therefore, the net force tending to put the dresser in motion, \(F_{Net}\), is given as follows;

\(F_{Net}\) = The force applied by the man, C - The frictional force provided by the carpet which is the component of the weight resisting motion, A

\(F_{Net}\) = C - A = 20 N - 8 N = 12 N

\(F_{Net}\) = 12 N

The resulting net force, \(F_{Net}\) = 12 N.

The resultant force can be obtained by subtracting vector C from Vector A and the value of net force is 12 N. Hence, option (C) is correct.

Given data:

The weight of man is, W = 250 N.

The magnitude of applied force is, F = 20 N.

The magnitude of frictional force is, f = 8 N.

As per the given problem and the diagram let the applied force be denoted by vector A, Then,

Magnitude of Vector A = 20 N

And the frictional force be denoted by vector C. Then,

Magnitude of Vector C = 8 N

We know that the role of frictional force is to oppose the motion or to oppose the effect of applied force. Then the resultant force is given as,

\(F_{net} = F-f\\\\F_{net} = 20 - 8\\\\F_{net} = 12 \;\rm N\)

Thus, we can conclude that the resultant force can be obtained by subtracting vector C from Vector A and the value of net force is 12 N. Hence, option (C) is correct.

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Elasticity is of significant importance in the everyday lives of businesses and consumers as it helps them understand and respond to changes in prices and demand for goods or services. By considering elasticity, businesses can make informed decisions regarding pricing strategies, production levels, and resource allocation. Consumers, on the other hand, can assess the impact of price changes on their purchasing decisions and adjust their consumption patterns accordingly.

Elasticity, specifically price elasticity of demand, measures the responsiveness of consumer demand to changes in price. It indicates the percentage change in quantity demanded resulting from a one percent change in price. Understanding price elasticity allows businesses to determine how sensitive consumers are to changes in price and adjust their pricing strategies accordingly.

For example, let's consider the market for gasoline. Gasoline is a highly price-sensitive good, meaning that changes in its price have a significant impact on consumer demand. If the price of gasoline increases, consumers may reduce their consumption and seek alternatives such as carpooling or using public transportation. In this scenario, businesses need to consider the price elasticity of gasoline to predict and respond to changes in consumer behavior. They might lower prices to stimulate demand or introduce more fuel-efficient options to cater to price-conscious consumers.

In conclusion, elasticity matters because it provides valuable insights into the dynamics of supply and demand, enabling businesses and consumers to make informed decisions in response to price changes. By understanding elasticity, businesses can adapt their strategies to maintain competitiveness, while consumers can optimize their purchasing choices based on price sensitivity.

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In the context of quadratic equations, a root refers to a specific value that satisfies the equation when substituted into it, while a solution refers to the complete set of roots that satisfy the equation.

When solving a quadratic equation, the goal is to find the values of the variable that make the equation true. These values are called roots or solutions. However, there is a subtle difference between the two terms. A root is a single value that, when substituted into the quadratic equation, makes it equal to zero.

In other words, a root is a solution to the equation on an individual basis. For a quadratic equation of the form \(ax^2 + bx + c = 0\), each value of x that satisfies the equation and makes it equal to zero is considered a root.

On the other hand, a solution refers to the complete set of roots that satisfy the quadratic equation. A quadratic equation can have zero, one, or two distinct roots. If the equation has two different values of x that make it equal to zero, then it has two distinct roots.

If there is only one value of x that satisfies the equation, then it has a single root. In some cases, a quadratic equation may not have any real roots but can have complex roots.

In summary, a root is an individual value that satisfies the quadratic equation, while a solution encompasses the complete set of roots that satisfy the equation. The distinction between the two lies in the context of how they are used in solving quadratic equations.

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Using first order perturbation theory the correction to the ground state energy of the hydrogen atom is -13.6 eV. The perturbation is V^(r) = ϕ(r) - V^0(r)

To determine the correction to the ground state energy of the hydrogen atom using first-order perturbation theory, we need to calculate the perturbation V^ and then use it to compute the energy correction.

The perturbation V^ arises from the difference between the actual potential ϕ(r) and the potential due to a point-like proton, which is the potential used in the Hamiltonian H^0 of the hydrogen atom. Therefore, we have:

V^(r) = ϕ(r) - V^0(r)

where V^0(r) is the potential due to a point-like proton, given by:

V^0(r) = - Q/(4πϵ_0 r)

Note that the negative sign comes from the fact that the proton has a positive charge.

Now, let's substitute the expression for ϕ(r) in the equation for V^(r) and simplify:

V^(r) = { Q/(8πϵ_0 R) } ( 3 - r^2/R^2 ) for r ≤ R

V^(r) = - { Q/(4πϵ_0 r) } for r > R

The first expression applies for distances r less than or equal to the radius R of the homogeneous charge distribution, while the second expression applies for distances greater than R.

To calculate the energy correction, we need to evaluate the expectation value of V^ with respect to the ground state wave function ψ_1s of the hydrogen atom, which we assume to be known:

ΔE = ⟨ψ_1s| V^ |ψ_1s⟩

Using the radial part of the 1s wave function, which depends only on the distance r from the proton, we can write:

ΔE = 4π ∫_0^∞ r^2 ψ_1s(r) V^(r) ψ_1s(r) dr

The integral limits cover the entire range of possible distances from the proton.

To evaluate this integral, we need to use the expression for the 1s wave function of the hydrogen atom, which is:

ψ_1s(r) = (1/πa^3)^(1/2) e^(-r/a)

where a is the Bohr radius.

Substituting this into the expression for ΔE and performing the integral, we obtain:

ΔE = { Q^2 a^3 / (2 πϵ_0 R^3) } [ 1 - (15/4) (a/R)^2 ]

Note that the correction is proportional to Q^2, the square of the proton charge, and inversely proportional to R^3, the cube of the radius of the charge distribution. This makes sense, as a larger charge or a smaller radius of the distribution should result in a larger perturbation.

Finally, substituting the values for Q and R, we obtain:

ΔE = 5.6 x 10^-22 eV

This correction is very small compared to the ground state energy of the hydrogen atom, which is -13.6 eV. However, it is still measurable in experiments and is an important correction to take into account in some contexts.

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Answer: 8v

Explanation:

The total voltage drop across the first and second resistor is 8 V, hence option A is correct.

Voltage is the fluctuation in electric potential between the two places. It is sometimes produced by electric pressure, electric tension, or voltage source. The work required to move a test charge between two places in a static electric field corresponds to this. The derived measure for voltage in the International System of Units is called a volt. Work per unit energy is expressed in SI units as joules per coulomb, with 1 volt equaling 1 joule per 1 coulomb.

To detect the voltages between two locations in a circuit, use a voltmeter. A common reference point, like the system's foundation, is frequently utilized as one of the points.

A voltage can indicate either a supply of energy or its loss, dissipation, or storage.

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Which example shows Pascal's principle a hydraulic jack .

What is a hydraulic jack?

A hydraulic jack is a device used to lift heavy objects or materials by using a hydraulic cylinder to generate a large amount of force. It works by using a pump to transfer fluid from a reservoir into a cylinder, which in turn applies pressure to a piston.

When the pressure is high enough, the piston will push against the object it is lifting, allowing the user to raise or lower the object. Hydraulic jacks are often used for automotive repair, construction, and other heavy-lifting applications.

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Answer:

usa

Explanation:

The refractive index of 2.14 indicates that the light in the liquid is slowed down by a factor of 2.14 compared to when it travels in a vacuum. The refractive index of a substance is a measure of how much light is slowed down or bent when it passes through that substance compared to when it travels in a vacuum.

The refractive index of a substance is a measure of how much light is slowed down or bent when it passes through that substance compared to when it travels in a vacuum. In this case, light travels 3.32 km in a vacuum and 1.55 km in the liquid during the same time.
To find the refractive index of the liquid, we can use the formula: Refractive index = distance traveled in vacuum / distance traveled in the liquid.
Using the given values, the refractive index of the liquid would be:
Refractive index = 3.32 km / 1.55 km = 2.14.
So, the refractive index of the liquid is 2.14.
To understand this better, let's consider an example. Imagine a beam of light traveling through a vacuum. It would travel straight without any deviation. But when the same beam of light enters the liquid, it slows down and bends slightly due to the change in the medium. The refractive index tells us how much the light bends or slows down in that particular substance compared to vacuum.
In this case, the refractive index of 2.14 indicates that the light in the liquid is slowed down by a factor of 2.14 compared to when it travels in a vacuum.

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Answer:

The mass, size, and shape of the object are not a factor in describing the motion of the object. So all objects, regardless of size or shape or weight, free fall with the same acceleration. In a vacuum, a beach ball falls at the same rate as an airliner.

Explanation:

ALL objects (regardless of their mass) free fall with the same acceleration - 9.8 m/s/s. This particular acceleration value is so important in physics that it has its own peculiar name - the acceleration of gravity

Answer:

I believe the correct answer is 30m/s/s

a) the current in the wire is 4.547 kA

b) the fraction of power lost in transmission is 0.000529%.

(a) Current in the wire

I = V / R = V / (ρL / A)= V × A / ρL, where A is the cross-sectional area of the wire and ρ is its resistivity.

The resistivity of copper is 1.7 × 10⁻⁸ Ωm.

Area, A = πr², where r is the radius of the wire.A single wire implies the circuit is incomplete and current flows from the power plant on a single wire with resistance through the city, and returns via the ground, which has negligible resistance.

Therefore, resistance, R = ρL / A= (1.7 × 10⁻⁸ Ωm × 40 × 10³ m) / (πr²)= 2.156 × 10⁻⁴ / r²

I = V × A / ρL= V × πr² / (1.7 × 10⁻⁸ Ωm × 40 × 10³ m)∴

I = (115 × 10³ V) × πr² / (1.7 × 10⁻⁸ Ωm × 40 × 10³ m)≈ 4.547 kA

(b) Fraction of power lost in transmission

The power lost in transmission is given by

P(loss) = I²R= I²ρL / A= I² × (1.7 × 10⁻⁸ Ωm × 40 × 10³ m) / (πr²)∴

P(loss) = (4.547 × 10³ A)² × (1.7 × 10⁻⁸ Ωm × 40 × 10³ m) / (πr²)≈ 529 W

As such, the fraction of power lost in transmission is

P(loss) / P= 529 W / 1000 MW× 100%= 5.29 × 10⁻⁴ %≈ 0.000529%

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In conclusion, we have converted the measurements from kilometers to meters, centimeters to hectometers, millimeters to dekameters, and dekameters to decimeters. We have also solved addition, subtraction, multiplication, and division problems involving the given measurements.

To convert the given measurements, we will use the metric system conversion factors. Here are the conversions:
a. 90 kilometers to meters:
1 kilometer = 1000 meters
Therefore, 90 kilometers = 90 * 1000 = 90,000 meters.
b. 250 centimeters to hectometers:
1 centimeter = 0.01 meter
1 hectometer = 100 meters
First, convert centimeters to meters: 250 centimeters * 0.01 = 2.5 meters.
Then, convert meters to hectometers: 2.5 meters / 100 = 0.025 hectometers.
c. 3,500 millimeters to dekameters:
1 millimeter = 0.001 meter
1 dekameter = 10 meters
First, convert millimeters to meters: 3,500 millimeters * 0.001 = 3.5 meters.
Then, convert meters to dekameters: 3.5 meters / 10 = 0.35 dekameters.
d. 10 dekameters to decimeters:
1 dekameter = 10 meters
1 decimeter = 0.1 meter
Convert dekameters to meters: 10 dekameters * 10 = 100 meters.
Then, convert meters to decimeters: 100 meters / 0.1 = 1000 decimeters.
Now, let's solve the addition and subtraction problems:
3 km 9 hm 9 dam 19 m + 7 km 2 dam:
Grouping like terms, we have:
(3 km + 7 km) + (9 hm + 2 dam) + 9 dam + 19 m
= 10 km + 11 hm + 9 dam + 19 m
= 10 km 11 hm 9 dam 19 m
5 sq km 95 ha 8,994 sq m - 11 sq km 11 ha 9,010 sq m:
Grouping like terms, we have:
(5 sq km - 11 sq km) + (95 ha - 11 ha) + (8,994 sq m - 9,010 sq m)
= -6 sq km + 84 ha - 16 sq m
= -6 sq km 84 ha - 16 sq m
44 m - 5 dm:
Convert decimeters to meters: 5 dm * 0.1 = 0.5 m
Subtract: 44 m - 0.5 m = 43.5 m
72 km 47 hm 2 dam - 11 km 55 hm:
Grouping like terms, we have:
(72 km - 11 km) + (47 hm - 55 hm) + 2 dam
= 61 km - 8 hm 2 dam
Now, let's solve the multiplication and division problem:
a. 3 km 5 hm × 15:
Grouping like terms, we have:
(3 km × 15) + (5 hm × 15)
= 45 km + 75 hm
= 45 km 75 hm
In conclusion, we have converted the measurements from kilometers to meters, centimeters to hectometers, millimeters to dekameters, and dekameters to decimeters. We have also solved addition, subtraction, multiplication, and division problems involving the given measurements.

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The best data about the surface topography of Venus has come from various missions and instruments sent by different space agencies. The first spacecraft to provide information about Venus was NASA's Mariner 2, which made a flyby in 1962.

However, it was the Soviet Venera missions that provided the most detailed information about the planet's surface in the 1970s and 1980s. The Venera probes used radar to map the surface, revealing that Venus has vast volcanic plains, impact craters, and mountain ranges. Later missions, such as NASA's Magellan spacecraft in the 1990s, provided even more detailed maps of Venus' surface topography using advanced radar imaging techniques.

With these missions, scientists have been able to study the geology and morphology of Venus, including its thick atmosphere, which has made it difficult to observe the surface with visible light. Overall, the data collected from these missions has greatly improved our understanding of Venus and its unique topography.

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The level of flexibility will affect my performances in football. Football

requires some level of flexibility to do certain things.

Flexibility will enable me change speed and direction easily when there is a

counter attack by the opponents. It will also assist in using some techniques

such as adding more curve on the football with the feet in order to score

goals.

Flexibility will also ensure that there will be lesser injury concerns because there will be less sprains or other muscle related injuries.

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simple methods to carry a sufferer encompass the four-hand seat, backpack carry, ski pole or tree limb backpack carry, and coiled rope seat. In the first method, two rescuers interlock hands. Each rescuer first grasps his right wrist with his left hand.

A real root of the equation f(x) = x^2 - 2x - 5 = 0, found using the bisection method in five stages, is approximately x = -0.046875. To find a real root of the equation f(x) = x^2 - 2x - 5 = 0 using the bisection method, we can start by identifying an interval [a, b] that contains the root. Let's choose the interval [-3, 0], where f(a) = f(-3) = 4 and f(b) = f(0) = -5. Since f(a) and f(b) have opposite signs, there must be a root within this interval.

Stage 1:

- Start with interval [a, b] = [-3, 0]

- Calculate the midpoint c = (a + b) / 2 = (-3 + 0) / 2 = -1.5

- Evaluate f(c) = (-1.5)^2 - 2(-1.5) - 5 = -0.25

- Since f(c) has the same sign as f(a), replace a with c: [a, b] = [-1.5, 0]

Stage 2:

- Calculate the new midpoint c = (a + b) / 2 = (-1.5 + 0) / 2 = -0.75

- Evaluate f(c) = (-0.75)^2 - 2(-0.75) - 5 = -4.4375

- Since f(c) has the same sign as f(a), replace a with c: [a, b] = [-0.75, 0]

Stage 3:

- Calculate the new midpoint c = (a + b) / 2 = (-0.75 + 0) / 2 = -0.375

- Evaluate f(c) = (-0.375)^2 - 2(-0.375) - 5 = -2.7461

- Since f(c) has the same sign as f(a), replace a with c: [a, b] = [-0.375, 0]

Stage 4:

- Calculate the new midpoint c = (a + b) / 2 = (-0.375 + 0) / 2 = -0.1875

- Evaluate f(c) = (-0.1875)^2 - 2(-0.1875) - 5 = -1.2217

- Since f(c) has the same sign as f(a), replace a with c: [a, b] = [-0.1875, 0]

Stage 5:

- Calculate the new midpoint c = (a + b) / 2 = (-0.1875 + 0) / 2 = -0.09375

- Evaluate f(c) = (-0.09375)^2 - 2(-0.09375) - 5 = -0.6104

- Since f(c) has the same sign as f(a), replace a with c: [a, b] = [-0.09375, 0]

After five stages, the interval [a, b] has become [-0.09375, 0]. Since the interval is small, we can approximate the root as the midpoint of this interval:

Root ≈ (a + b) / 2 = (-0.09375 + 0) / 2 = -0.046875

Therefore, a real root of the equation f(x) = x^2 - 2x - 5 = 0, found using the bisection method in five stages, is approximately x = -0.046875.

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In a deep vacuum, the pressure exerted by the atmosphere on a gauge line is negligible or close to zero. A vacuum is defined as a region with a low gas pressure, typically much lower than atmospheric pressure.

In a deep vacuum, the pressure is significantly lower compared to atmospheric pressure. The atmosphere exerts pressure on objects due to the weight of the air above them. However, in a deep vacuum where air or any other gas is absent, there is no medium to exert pressure on the gauge line.

A vacuum is defined as a region with a low gas pressure, typically much lower than atmospheric pressure. In a deep vacuum, the pressure is close to zero or negligible. This means that the atmosphere does not exert any significant pressure on a gauge line placed in a deep vacuum.

It is important to note that the absence of pressure in a deep vacuum does not mean the absence of other effects, such as radiation pressure or gravitational forces, which may still be present depending on the specific conditions. However, in terms of atmospheric pressure, it is essentially nonexistent in a deep vacuum.

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Answer:

0.0013 m/s

Explanation:

Speed in inches per minute = 3 inches per minute

Speed in m/s =?

Next, we shall convert 3 inches per minute (3 in/min) to metre per minute.(m/min)

39 in/min = 1 m/min

Therefore,

3 in/min = 3 in/min × 1 m/min / 39 in/min

3 in/min = 1/13 m/min

Finally, we shall convert 1/13 m/min to m/s. This can be obtained as follow:

1 m/min = 1/60 m/s

Therefore,

1/13 m/min = 1/13 m/min × 1/60 m/s / 1 m/min

1/13 m/min = 1/780 m/s

1/13 m/min = 0.0013 m/s

Thus, 3 in/min is equivalent to 0.0013 m/s.

Therefore the speed of the snail in m/s is 0.0013 m/s

Answer:

cities grow all around

making bunches of funny sounds

Explanation:

A simulation is a model that replicates how a current or proposed system functions, offering evidence for decision-making by allowing the testing of various scenarios or process changes.

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A lunar astronaut carries a 110 kg box and a 230 kg load. The forces required to move the containers straight up on the moon are enormous compared to the forces required to hoist them on Earth.

A forces is an influence with the capacity to change the motion of an object. When an object with mass moves away from rest, for example, a force can cause it to accelerate as its velocity increases. A push or a pull are two straightforward ways to demonstrate force. Since a force has both magnitude and direction, it is a vector quantity. It is computed using the SI unit of newton (N). The letter F stands for force (formerly P). The original wording of Newton's second law states that the net force acting on an item is equal to the rate of change of its momentum over time. This law states that if an object's mass stays constant, its acceleration should be directly proportional to the net force exerted on it and inversely proportional to the object's mass. Thrust, which increases an object's velocity; drag, which decreases an object's velocity; and torque, which modifies an object's rotational speed, are all ideas connected to force. Internal mechanical stress describes how these forces are distributed within the body. The adjacent regions are frequently put under stress by each expanded body part.

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Answer:

Equality is the state of being equal in rights word and oportunities

Answer:

800km/s

Explanation:

Initial momentum = final momentum

the total momentum is zero, Before the release of the asteroid , but Superman and the asteroid are not moving.

So, according to the Conservation of momentum the total momentum when the astronaut is been thrown will equals to zero . Then we can say

Initial momentum = final momentum

Because the momentum of the Superman immediately the asteroid is been thrown is equal to the momentum of the asteroid

Momentum =(mass ×velocity)

the mass of the asteroid i= 1000M

Given velocity = 800 m/s,

momentum =(1000M)(800 m/s)

= 800,000M m/s.

to get the answer, we need to divide by Superman's mass, M, which gives his recoil velocity of 800,000 m/s.

But we're told to convert to km/ s

We know that 1m/s=0.001km/s

=(800,000M m/s)× (0.001km/s)

=800km/s

Therefore, his recoil speed (in km/s) is 800km/s