A force accelerates a body of mass M.The same force applied to a second body produces three times the acceleration.What is the mass of the second body?
A)M
B)3M
C)M/3
D)9M
E)M/9

Question

Quizplus · Accepted Answer

According to Newton's second law of motion, F = ma, where F is the force applied, m is the mass of the body, and a is the resulting acceleration. 
Let's say the force applied is F and the mass of the first body is M. Then, 
F = Ma   ------(1) 
Now, if the same force is applied to a second body with mass m2, and it produces three times the acceleration, the equation becomes, 
F = 3m2a   ------(2) 
Dividing equation 1 by equation 2, we get, 
M/3m2 = a/a = 1 
Therefore, m2 = M/3, which is option C.

A Force Accelerates a Body of Mass M