The horizontal surface on which the objects slide is frictionless.If M = 1.0 kg and the magnitude of the force of the small block on the large block is 5.2 N,determine F.
A)6.0 N
B)9.0 N
C)7.8 N
D)4.8 N
E)4.1 N

Question

The horizontal surface on which the objects slide is frictionless.If M = 1.0 kg and the magnitude of the force of the small block on the large block is 5.2 N,determine F. 
A)6.0 N 
B)9.0 N 
C)7.8 N 
D)4.8 N 
E)4.1 N

Quizplus · Accepted Answer

The force of the small block on the large block is equal to the force of the large block on the small block due to Newton's third law. Thus, we have F = 5.2 N. To find the acceleration of the system, we need to find the net force on the system. The only force on the system is the force of the small block on the large block. Thus, we have Fnet = 5.2 N. Using Newton's second law, Fnet = MA, we can find the acceleration of the system to be A = Fnet / M = 5.2 N / 1.0 kg = 5.2 m/s^2. Since the surface is frictionless, the acceleration of the small block and the large block will be the same. Thus, we have A = a = 5.2 m/s^2. To find the force F required to push the large block, we can use the equation F = MA = 1.0 kg x 5.2 m/s^2 = 5.2 N. Therefore, the best choice is C, 7.8 N.

The Horizontal Surface on Which the Objects Slide Is Frictionless