A body of mass 4kg is acted on by a constant force of 12N for 3 seconds. The kinetic energy gained by the body at the end of the time is
Take Free Practice Test On 2026 JAMB UTME, Post UTME, WAEC SSCE, GCE, NECO SSCE
Correct Answer: Option B
Explanation:
K.E = 1/2MV2
Force, F = ma => a = F/m = 12/4 = 3ms-2
But a = (V-U) / t => V = u + at
If the initial velocity U = 0, then V = at = 3 x 3 = 9ms-2
∴ K.E, = 1/2ms-21/2 4 x 9 x 9 = 162J
K.E = 1/2MV2
Force, F = ma => a = F/m = 12/4 = 3ms-2
But a = (V-U) / t => V = u + at
If the initial velocity U = 0, then V = at = 3 x 3 = 9ms-2
∴ K.E, = 1/2ms-21/2 4 x 9 x 9 = 162J