If a 3 kg object is moving with a speed of 4 m/s and comes to a stop, what is th

If a 3 kg object is moving with a speed of 4 m/s and comes to a stop, what is the work done by friction?

If a 3 kg object is moving with a speed of 4 m/s and comes to a stop, what is the work done by friction?

Correct Answer: -24 J

Step 1: Identify the mass of the object. The mass (m) is 3 kg.
Step 2: Identify the speed of the object. The speed (v) is 4 m/s.
Step 3: Use the formula for kinetic energy: KE = 0.5 × m × v².
Step 4: Plug in the values: KE = 0.5 × 3 kg × (4 m/s)².
Step 5: Calculate (4 m/s)², which is 16 m²/s².
Step 6: Multiply 0.5 × 3 kg × 16 m²/s² to get 24 J.
Step 7: The initial kinetic energy of the object is 24 J.
Step 8: When the object comes to a stop, all of this energy is used to overcome friction.
Step 9: The work done by friction is equal to the negative of the initial kinetic energy, which is -24 J.

Kinetic Energy – The energy an object possesses due to its motion, calculated using the formula KE = 0.5 × m × v².
Work-Energy Principle – The principle stating that the work done on an object is equal to the change in its kinetic energy.
Friction – A force that opposes the motion of an object, doing negative work when it brings the object to a stop.