Work Done by a Constant Force and a Variable Force NEET Questions

Work Done by a Constant Force and a Variable Force MCQ Questions

1.
Which of the following is the correct definition of a conservative force?
A.
A force that always acts in the direction of motion
B.
A force for which work done depends only on the initial and final positions, not the path taken
C.
A force that conserves momentum
D.
A force that does zero work on any body
ANSWER :
B. A force for which work done depends only on the initial and final positions, not the path taken
2.
Work done by a conservative force along a closed path is:
A.
Positive
B.
Negative
C.
Zero
D.
Depends on the speed of the body
ANSWER :
C. Zero
3.
Which of the following forces is NON-CONSERVATIVE?
A.
Gravitational force
B.
Spring (elastic) force
C.
Frictional force
D.
Electrostatic force
ANSWER :
C. Frictional force
4.
A force F on a particle moving in a straight line varies with distance d. The work done by the force in displacing the particle from d=0 to d=12 m is:
A.
21 J
B.
26 J
C.
13 J
D.
18 J
ANSWER :
B. 26 J
5.
For a conservative force F(x), the potential energy function V(x) is related by:
A.
F(x) = dV/dx
B.
F(x) = โˆ’dV/dx
C.
F(x) = V(x) ยท x
D.
F(x) = โˆ’V(x)/x
ANSWER :
B. F(x) = โˆ’dV/dx
6.
A block is pushed along a rough horizontal surface from point A to point B by two different paths. The work done by friction:
A.
Is the same for both paths
B.
Is greater for the longer path
C.
Is zero for both paths
D.
Depends only on the endpoints A and B
ANSWER :
B. Is greater for the longer path