a = 25/1.5
Or, a = 16.67 m/s
2
Since, we know initial and final velocities and acceleration as well we can use kinematic equation
v
2
= u
2
- 2as -------------- (3)
to solve for displacement.
Where
S is the displacement of the car; We have taken the negative sign for acceleration here due to the fact
that acceleration is negative. Putting the values of v, u, a in equation 3 we get
0 = 25
2
- 2 × 16.67 × S
Or, 25
2
= 2 × 16.67 × S
Or, S = 25
2
/(2*16.67)
Or, S = 625/33.34
Or, S = 18.75m
Hence, B is the correct answer option.
Question 3
Net force acting on a body moving with constant velocity is zero. Which of the following is
incorrect?
A. Body will slow down
B. Body will move faster
C. Body will stop
D. Body will continue moving with same velocity
E. Body will accelerate
Correct Answer: D
Explanation:
A body moving with constant velocity or at rest is the condition of static equilibrium. For static
equilibrium, we need balanced force that means all the forces acting on the body balance each other
and in this way the net force acting on the body becomes zero. Therefore, only option D is correct
amongst the first four the options given above. Body cannot accelerate, as acceleration is time rate of
change of velocity. If velocity is remaining constant, the acceleration will become zero. Therefore, E is
an incorrect option.
Question 4
Two blocks of masses M and 4 M are moving under the effect of the same force, F on a
frictionless table as shown below. What would be acceleration of the smaller mass? (Assume
smaller mass is at rest with respect to the larger mass)
A. F/4M
B. F/M