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A truck of 2,000 kg mass moving at a velocity of 12 meter per second slides 15 m before it comes to a stop after applying the brakes.

find the resisting force of the brakes​

User Liala
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1 Answer

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To find the resisting force of the brakes, we need to use the equation for kinetic friction:

Ffriction = friction coefficient x normal force

We can calculate the normal force as the weight of the truck, which is equal to its mass times the acceleration due to gravity:

normal force = mass x gravity = 2000 kg x 9.81 m/s^2 = 19,620 N

We can also use the equation for kinetic energy to find the initial kinetic energy of the truck:

kinetic energy = 1/2 x mass x velocity^2 = 1/2 x 2000 kg x (12 m/s)^2 = 144,000 J

When the truck comes to a stop, all of its initial kinetic energy is dissipated by the resisting force of the brakes over a distance of 15 meters. Therefore, we can use the work-energy principle to find the resisting force of the brakes:

work done by resisting force = change in kinetic energy

resisting force x distance = 144,000 J

resisting force = 144,000 J / 15 m = 9,600 N

Thus, the resisting force of the brakes is 9,600 N.

User Steve Yost
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