Consider the following three situations: SITUATION 1: Three blocks are sitting o
ID: 1550376 • Letter: C
Question
Consider the following three situations:
SITUATION 1: Three blocks are sitting on a smooth horizontal surface as shown, with block C in contact with a brick wall. A horizontal force is applied to block A.
SITUATION 11: This is the same as Situation I, except that there is no wall to prevent the blocks from moving. The surface is frictionless.
SITUATION 111: This is the same as Situation II, except that now there is sufficient friction between the blocks and the surface to prevent motion. If block C were removed, blocks A and B would remain at rest.
In all three situations the magnitude of the applied force is the same.
a. In which of the situations are the blocks accelerating? Explain.
b. In which of the situations is the net force on block C the largest? Explain.
c. In which of the situations is the force on block B due to block C the largest? Explain.
d. Which of your answers depend upon the masses of the blocks? Explain.
SITUATION I SITUATION II SITUATION III (at res)Explanation / Answer
(A) In situation II there will be acceleration .
In situation II , Let F is the applied force so .
acceleration a=F/(MA+MB+MC)
but in case III we have frictional force acting in opposite direction of the force so the system will remain in rest .
In situation I there is wall which will oppose the motion so there is no net force acting on the body.
(B) In situation II
Here there is no force acting on the body C in opposite direction of applied force .
But in other situations like in situation I : there is force due to wall which is in opposite direction.
in situation III : there is frictional force which acts in such a direction that it opposes the motion Hence it will also act in opposite of applied force .
(C)The force on block B due to C is largest in situation III because in this case there is wall at the end so there will be no motion in the system so the body will get equall and opposite reaction force in this situation.
(D)
When we need to calculate the acceleration we need Mass for that .