Question

A 60.0 kg object is moving east at 8.00 m/s, and then slows down to 4.00 m/s. How much work was done?

Answer 1

Answer:

A

-1440J

Explanation:

Hello,

This question requires us to calculate the work done on a object to move it from point A to point B

Data

Mass = 60kg

Initial velocity (V1) = 8.0m/s

Final velocity (V2) = 4.0m/s

Workdone on an object is equal to force applied on the object to move it through a particular distance.

Work done = force × distance

Force (F) = mass × acceleration

Distance = s

F = Ma

Work done = M× a × s

But a = velocity (v) / time (t)

Work done = mvs / t

But velocity = distance/ time

Work done = mv × v/

Work done = mv²

Work done = ½mv²

Workdone = ½M(V2² - V1²)

Workdone = ½ × 60 (4² - 8²)

Work done = 30 × (16 - 64)

Workdone = 30 × (-48)

Work done = -1440J

Work done = -1.44kJ

The workdone on the object is equal to -1.44kJ