Question
Physics Question on Friction
A block of mass 100 kg slides over a distance of 10 m on a horizontal surface. If the coefficient of friction between the surfaces is 0.4, then the work done against friction (in J) is:
A
4500 J
B
50000 J
C
4200 J
D
4000 J
Answer
4000 J
Explanation
Solution
Given Data: - Mass m = 100 kg - Distance s = 10 m - Coefficient of friction μ = 0.4
Calculate the Frictional Force f : - The frictional force is given by f = μmg,
f = 0.4 × 100 × 10 = 400 N
Calculate the Work Done Against Friction W : - Work done W = f × s,
W = 400 × 10 = 4000 J
So, the correct answer is: 4000 J