Question

The figure below shows overhead views of four situations in which two forces act on the same block of mass m=1 kg and accelerate the block across a frictionless floor. Rank the situations according to the magnitudes of the acceleration of the block,

• A. 1,2,3,4
• B. 1,3,4,2
• C. 1,4,3,2
• D. 1,2,4,3

Answer 1

The correct option is C

1,4,3,2

The largest acceleration occurs when the two forces add up to the largest net force. That is, when the two forces point in the same direction. So, (1) must be the largest. The smallest acceleration occurs when they point in the opposite direction. So, (2) must be the smallest. Let's compare (3) and (4). By adding the vectors using parallelogram method the net force in (4) is larger than the net force in (3).