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Westkost [7]
3 years ago
9

A force of 70 N is applied to a 28 kg rock causing it to slow down from 25 m/s to 15 m/s, a change in velocity of 10 m/s. How lo

ng was that force applied?
Physics
1 answer:
maksim [4K]3 years ago
7 0

Answer: 4 s

Explanation:

Given

The applied force is 70 N

mass of the rock is 28 kg

initial velocity u=25\ m/s

final velocity v=15\ m/s

Deceleration provided by force is

a=-\dfrac{70}{28}=-2.5\ m/s^2

using the equation of motion

v=u+at\\\Rightarrow 15=25-2.5t\\\Rightarrow 2.5t=10\\\Rightarrow t=4\ s

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A particle starts from rest and has an acceleration function 5 − 10t m/s2 . (a) What is the velocity function? (b) What is the p
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Explanation:

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A particle starts from rest and has an acceleration function as :

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