A 2 kg block is pulled along a rough floor by a horizontal force of 20 N. Friction is 4 N. What is the block's acceleration?
Answer and explanation
Correct answer: A. 8 m/s^2
- Step 1: Net force = 20 - 4 = 16 N.
- Step 2: a = F_net / m = 16 / 2 = 8 m/s^2.
Answer
8 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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