Question

A 1000 kg object, which is moving initially at 25 m/s, is brought to rest over a distance of 80 m by the frictional force between the object and the surface. How large is the frictional force?

a. 3.9 kN

b. 12 kN

c. 8.0 kN

d. 4.8 kN

e. none of the given answers is correct

Answer #1

Deceleration experienced by the object

Using Kinematic equation

Negative sign indicates deceleration

By Newton's Second law of motion

As frictional force is always in opposite direction to the direction of motion

**OPTION A**

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