# A cord is used to vertically lower a block of mass m by a distance d at a constant downward acceleration of $\frac{\text{'}\mathrm{g}\text{'}}{4}$. The work done by the chord on the block will be: 1.  $\frac{3}{4}$mgd 2.  -$\frac{3}{4}$mgd 3.  $\frac{1}{4}$mgd 4.   -$\frac{1}{4}$mgd

Subtopic:  Work done by constant force |
68%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

An engine pumps liquid of density d continuously through a pipe of cross-sectional area A. If the speed with which liquid passes through the pipe is v, then the rate at which kinetic energy is being imparted to the liquid by the pump is:

 1 ${\mathrm{Adv}}^{2}$ 2 $\frac{1}{2}{\mathrm{Adv}}^{2}$ 3 $\frac{1}{2}{\mathrm{Adv}}^{3}$ 4 $\frac{1}{2}\mathrm{Adv}$
Subtopic:  Power |
78%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The work done in increasing the length of a massless spring from its natural length 15 cm to 15.1 cm is 20 J. Work done in increasing the length from 15.1 cm to 15.2 cm will be:

 1 20 J 2 40 J 3 60 J 4 80 J
Subtopic:  Elastic Potential Energy |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A body of mass m moving at a certain speed suffers a perfectly inelastic collision with a body of mass M at rest. The ratio of the final kinetic energy of the system to the initial kinetic energy will be:

 1 $$m \over {m + M}$$ 2 $$M \over {m + M}$$ 3 $${m + M} \over m$$ 4 $${m + M} \over M$$
Subtopic:  Collisions |
61%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

An automobile of mass m accelerates from rest, while the engine supplies constant power P. The speed of the automobile as a function of time is given by:

1.

2.

3.

4.

Subtopic:  Power |
84%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The potential energy of a particle of mass 1 kg free to move along the X-axis is given by $$U(x) = (3x^2-4x+6)~\text{J}$$. The force acting on the particle at x = 0 will be:

1.  2$\stackrel{^}{\mathrm{i}}$ N

2.  -4$\stackrel{^}{\mathrm{i}}$ N

3.  5$\stackrel{^}{\mathrm{i}}$ N

4.  4$\stackrel{^}{\mathrm{i}}$ N

Subtopic:  Potential Energy: Relation with Force |
61%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Work done by frictional force during walking of a man is:

1.  Positive

2.  Negative

3.  Zero

4.  Maybe positive or negative

Subtopic:  Concept of Work |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A particle is moving such that the potential energy U varies with position in metre as U (x) = ($4{\mathrm{x}}^{2}$ - 2x + 50) J. The particle will be in equilibrium at:
1. x = 25 cm
2. x = 2.5 cm
3. x = 25 m
4. x = 2.5 m

Subtopic:  Potential Energy: Relation with Force |
78%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Select the incorrect statement about potential energy:

 1 A change in potential energy is equal to work done against the internal conservative force. 2 A change in potential energy is independent of the reference point. 3 A change in potential energy depends on the reference frame. 4 The potential energy at a point is not unique.

Subtopic:  Gravitational Potential Energy |
50%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A block of mass m is moving with speed v towards a spring block system. If the collision is perfectly inelastic, then the maximum compression in the spring will be:

1.  $\mathrm{v}\sqrt{\frac{\mathrm{m}}{\mathrm{k}}}$

2.  $\mathrm{v}\sqrt{\frac{2\mathrm{m}}{\mathrm{k}}}$

3.  $\mathrm{m}\sqrt{\frac{\mathrm{v}}{2\mathrm{k}}}$

4.  $\mathrm{v}\sqrt{\frac{\mathrm{m}}{2\mathrm{k}}}$

Subtopic:  Collisions |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints