A 4 kg block is pulled along a rough floor by a horizontal force of 50 N. Friction is 10 N. What is the block's acceleration?
Answer and explanation
Correct answer: C. 10 m/s^2
- Step 1: Net force = 50 - 10 = 40 N.
- Step 2: a = F_net / m = 40 / 4 = 10 m/s^2.
Answer
10 m/s^2.
Why not the others: Acceleration depends on the net force; ignoring friction, adding it, or using friction alone gives the other values.
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