Question

Which would require a greater force-accelerating a 3 kg mass at 6m/s or 4 kg mass at 4m/s?

Answer 1

To determine the force we can calculate them independantly


For first situation

F=ma = 3×6= 18 N

For second situation
F= ma= 4×4 = 16 N

Hence the 3 kg body requires more force.

Answer 2

First Situation,
F=mxa
F=3x6 = 18N

Second Situation,
F=mxa
F=4x4 =16N
So, the grater force is produced by 1'st object