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Determine the amount of work you would need to do in order to stop a 1100kg car with 1400J of kinetic energy.

User Troy D
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2 Answers

6 votes

The amount of work you would need to do in order to stop a 1100kg car with 1400J of kinetic energy is 1400J.

In order to determine the amount of work needed to stop a 1100kg car with 1400J of kinetic energy, we can use the work-energy theorem.

The work done on an object is equal to the change in its kinetic energy.

Since the car is brought to a stop, its final kinetic energy is 0J.

Therefore, the work done to stop the car is equal to the initial kinetic energy.

So, the work done = 1400J

User Hiroga
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4.8k points
6 votes

Answer:

W = -1400 J

Step-by-step explanation:

Let's use the relationship between work and kinetic energy

W = ΔK

kinetic energy is

K = ½ m v²

therefore in this case

K₀ = 1400 J

Thus

W = 0 -1400

W = -1400 J

The negative sign indicates that the work is done against the energy, that is, in the opposite direction to the movement

User BrianLegg
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4.4k points