A positive point charge is released from rest at a distance ro from a positive line charge with uniform density. The speed (v) of the point charge, as a function of instantaneous distance r from line charge, is proportional to:

\({\rm{v}} \propto {\rm{ln}}\left( {\frac{{\rm{r}}}{{{{\rm{r}}_{\rm{o}}}}}} \right)\)

\({\rm{v}} \propto {{\rm{e}}^{ + {\rm{r}}/{{\rm{r}}_{\rm{o}}}}}\)

\({\rm{v}} \propto \sqrt {{\rm{ln}}\left( {\frac{{\rm{r}}}{{{{\rm{r}}_{\rm{o}}}}}} \right)} \)

\({\rm{v}} \propto {\rm{ln}}\left( {\frac{{\rm{r}}}{{{{\rm{r}}_{\rm{o}}}}}} \right)\)

\({\rm{v}} \propto \left( {\frac{{\rm{r}}}{{{{\rm{r}}_{\rm{o}}}}}} \right)\)

A particle ‘P’ is formed due to a completely inelastic collision of particles ‘x’ and ‘y’ having de-Broglie wavelengths ‘λx’ and ‘λy’ respectively. If x and y were moving in opposite directions, then the de-Broglie wavelength of ‘P’ is:

\({\rm{}}\frac{{{\lambda _x}{\lambda _y}}}{{{\lambda _x} + {\lambda _y}}}\)

\(\frac{{{\lambda _x}{\lambda _y}}}{{\left| {{\lambda _x} - {\lambda _y}} \right|}}\)

Mechanical energy is equal to:

Kinetic energy + Chemical energy

Kinetic energy + Potential energy

Kinetic energy + Electrical energy

A lorry and a car moving with the same kinetic energy are brought to rest by applying the same retarding force. Then:

lorry will come to rest in a shorter distance

car will come to rest in a shorter distance

in order to know which one will come to rest in a shorter distance, one needs to know the masses of the lorry and the car

both come to rest in same distance

A body of mass m1 moving with an unknown velocity of \({v_1}\hat i\;\), undergoes a collinear collision with a body of mass m2 moving with velocity \({v_2}\hat i\). After the collision, m1 and m2 move with velocities of \({v_3}\hat i\;{\rm{and}}\;{v_4}\hat i\) respectively. If m2 = 0.5m1 and v3 = 0.5v1, then v1 is:

\({{\rm{v}}_4} - \frac{{{{\rm{v}}_2}}}{4}\)

\({{\rm{v}}_4} - \frac{{{{\rm{v}}_2}}}{2}\)

\({{\rm{v}}_4} - \frac{{{{\rm{v}}_2}}}{4}\)

On body work is done only when: _____.

It moves through a certain distance.

It provides energy boost through a mechanical effect.

Displacement takes place there.

It moves through a certain distance.

Given the current i(t) and voltage v(t) of a circuit element, the power p(t) and energy w(t) are given by:

p(t) = v(t).i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t v\left( \tau \right)d\tau \)

p(t) = v(t).i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t i\left( \tau \right)d\tau \)

p(t) = v(t).i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t p\left( \tau \right)d\tau \)

p(t) = v(t).i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t v\left( \tau \right)d\tau \)

p(t) = v(t) + i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t p\left( \tau \right)d\tau \)

In which case, positive work is done with least resistance?

While a helicopter is rising up from the ground

While there is electric current in a conductor

While a ball is rolling on a horizontal levelled floor

While a ripe fruit is falling from a tree

While a helicopter is rising up from the ground

Identify the correct statement from among the following

Work and kinetic energy do not have the same unit

Work is equal to power per unit time.

Work and potential energy have the same unit

133 + Mcqs in Work, Power and Energy in UPSEE Page 1 McqOptions

1.	Physical quantity of _____ is measured in watt.
A.	kinetic energy
B.	power
C.	momentum
D.	impulse
Answer» C. momentum

Discussion

2.	A pump is required to lift 600 kg of water per minute from a well 25 m deep and to eject it with a speed of 50 m / s. If g = 10 m / s2, the power required to perform the above task is
A.	20 kW
B.	15 kW
C.	10 kW
D.	22.5 kW
Answer» C. 10 kW

Discussion

3.	A wedge of mass M = 4m lies on a frictionless plane. A particle of mass m approaches the wedge with speed v. There is no friction between the particle and the plane or between the particle and the wedge. The maximum height climbed by the particle on the wedge is given by:
A.	\(\frac{{{v^2}}}{g}\)
B.	\(\frac{{2{v^2}}}{{7g}}\)
C.	\(\frac{{2{v^2}}}{{5g}}\)
D.	\(\frac{{{v^2}}}{{2g}}\)
Answer» D. \(\frac{{{v^2}}}{{2g}}\)

Discussion

4.	Find the energy possessed by an object of mass 14 kg when it is at a height of 5 m above the ground Given g = 9.8 ms-2
A.	528 J
B.	668 J
C.	686 m
D.	686 J
Answer» E.

Discussion

5.	Energy is the capability or ability to
A.	do work
B.	cause gravity
C.	destroy charge
D.	increase time
Answer» B. cause gravity

Discussion

6.	A passenger train of length 60 m travels at a speed of 80 km/hr. Another freight train of length 120 m travels at a speed of 30 km/hr. The ratio of times taken by the passenger train to completely cross the freight train when: (i) they are moving in the same direction and (ii) in the opposite direction is
A.	\(\frac{3}{2}\)
B.	\(\frac{{25}}{{11}}\)
C.	\(\frac{{11}}{5}\)
D.	\(\frac{5}{2}\)
Answer» D. \(\frac{5}{2}\)

Discussion

7.	A freely falling body takes 4 s to reach the ground. One second after release, the percentage of its potential energy, that is still retained is
A.	25%
B.	37.5%
C.	93.75%
D.	6.25%
Answer» D. 6.25%

Discussion

8.	A block of mass m is kept on a platform which starts from rest with constant acceleration \(\frac{g}{2}\) upwards as shown in figure. Work done by normal reaction on block in time t is
A.	\(\frac{{m{g^2}{t^2}}}{8}\)
B.	\(\frac{{3m{g^2}{t^2}}}{8}\)
C.	0
D.	\(- \frac{{m{g^2}{t^2}}}{8}\)
Answer» C. 0

Discussion

9.	A positive point charge is released from rest at a distance ro from a positive line charge with uniform density. The speed (v) of the point charge, as a function of instantaneous distance r from line charge, is proportional to:
A.	\({\rm{v}} \propto {{\rm{e}}^{ + {\rm{r}}/{{\rm{r}}_{\rm{o}}}}}\)
B.	\({\rm{v}} \propto \sqrt {{\rm{ln}}\left( {\frac{{\rm{r}}}{{{{\rm{r}}_{\rm{o}}}}}} \right)} \)
C.	\({\rm{v}} \propto {\rm{ln}}\left( {\frac{{\rm{r}}}{{{{\rm{r}}_{\rm{o}}}}}} \right)\)
D.	\({\rm{v}} \propto \left( {\frac{{\rm{r}}}{{{{\rm{r}}_{\rm{o}}}}}} \right)\)
Answer» C. \({\rm{v}} \propto {\rm{ln}}\left( {\frac{{\rm{r}}}{{{{\rm{r}}_{\rm{o}}}}}} \right)\)

Discussion

10.	A man of 25 kg weight climbs 25 stairs in 20 seconds. If the height of each stair is 40 cm, find the power (g = 10 m/s2)
A.	125 watt
B.	25 watt
C.	5 watt
D.	100 watt
Answer» B. 25 watt

Discussion

11.	A rocket has to be launched from earth in such a way that it never returns. If E is the minimum energy delivered by the rocket launcher, what should be the minimum energy that the launcher should have if the same rocket is to be launched from the surface of the moon? Assume that the density of the earth and the moon are equal and that the earth's volume is 64 times the volume of the moon.
A.	\(\frac{{\rm{E}}}{{64}}\)
B.	\(\frac{{\rm{E}}}{{32}}\)
C.	\(\frac{{\rm{E}}}{4}\)
D.	\(\frac{{\rm{E}}}{{16}}\)
Answer» E.

Discussion

12.	If the work done is zero, then the angle between the force and displacement is:
A.	45 degrees
B.	180 degrees
C.	0 degree
D.	90 degrees
Answer» E.

Discussion

13.	If two objects, whose masses are 'm' and '9m', are moving with equal kinetic energy, find the ratio of their linear momentum.
A.	1 : 9
B.	1 : 3
C.	9 : 1
D.	3 : 1
Answer» C. 9 : 1

Discussion

14.	A 2 mW laser operates at a wavelength of 500 nm. The number of photons that will be emitted per second is:[Given Planck’s constant h = 6.6 × 10-34 Js, speed of light c = 3.0 × 108 6m/s]
A.	5 × 1015
B.	1.5 × 1016
C.	2 × 1016
D.	1 × 1016
Answer» B. 1.5 × 1016

Discussion

15.	A body is thrown vertically upwards. During its rise the potential energy _______ and the kinetic energy _______.
A.	decreases, decreases
B.	increases, decreases
C.	remains same, remains same
D.	decreases, increases
Answer» C. remains same, remains same

Discussion

16.	An α-particle of mass m suffers one-dimensional elastic collision with a nucleus at rest of unknown mass. It is scattered directly backwards losing 64% of its initial kinetic energy. The mass of the nucleus is
A.	1.5 m
B.	4 m
C.	3.5 m
D.	2 m
Answer» C. 3.5 m

Discussion

17.	5.5 kwh = ?
A.	14.0 × 106 J
B.	19.8 × 106 J
C.	14.4 × 108 J
D.	14.4 × 105 J
Answer» C. 14.4 × 108 J

Discussion

18.	An object of mass 1 Kg is moving a velocity 10 m/s. Find the kinetic energy of the object.
A.	5 J
B.	100 J
C.	10 J
D.	50 J
Answer» E.

Discussion

19.	An electric iron of resistance 20 ohm takes a current of 5 A. The heat flow in 30 s is:
A.	\(1.5 \times 10^4 \ J\)
B.	\(2.5 \times 10^2 \ J\)
C.	\(1.5 \times 10^5 \ J\)
D.	\(1.5 \times 10^2 \ J\)
Answer» B. \(2.5 \times 10^2 \ J\)

Discussion

20.	A particle starts from the origin at time t = 0 and moves along the positive X -axis. The graph of velocity with respect to time is shown in figure. What is the position of the particle at time t = 5s?
A.	6 m
B.	3 m
C.	10 m
D.	9 m
Answer» E.

Discussion

21.	By applying the brakes without causing a skid, the driver of a car is able to stop within a distance of 5m, if it is going at 36 kmph. If the car were going at 72 kmph, using the same brakes, he can stop the car over a distance of:
A.	10 m
B.	20 m
C.	40 m
D.	2.5 m
Answer» C. 40 m

Discussion

22.	A particle ‘P’ is formed due to a completely inelastic collision of particles ‘x’ and ‘y’ having de-Broglie wavelengths ‘λx’ and ‘λy’ respectively. If x and y were moving in opposite directions, then the de-Broglie wavelength of ‘P’ is:
A.	\({\rm{}}\frac{{{\lambda _x}{\lambda _y}}}{{{\lambda _x} + {\lambda _y}}}\)
B.	\(\frac{{{\lambda _x}{\lambda _y}}}{{\left\| {{\lambda _x} - {\lambda _y}} \right\|}}\)
C.	λx - λy
D.	λx + λy
Answer» C. λx - λy

Discussion

23.	A shaft shown in the figure rotates at a rate of 100 rev/min against a constant torque of 1000 N-m. The power required to rotate the shaft is
A.	9.50 kW
B.	11.25 kW
C.	9.0 kW
D.	10.47 kW
Answer» E.

Discussion

24.	A body of mass 200g moves with the velocity of 20 m / s. The kinetic energy will be ___________?
A.	30 joules
B.	50 joules
C.	40 joules
D.	20 joules
Answer» D. 20 joules

Discussion

25.	Mechanical energy is equal to:
A.	Kinetic energy + Chemical energy
B.	Kinetic energy + Potential energy
C.	Kinetic energy + Heat energy
D.	Kinetic energy + Electrical energy
Answer» C. Kinetic energy + Heat energy

Discussion

26.	A machine does 20 Joules of work in 5 seconds. Its power is:
A.	100W
B.	0.25 W
C.	4 W
D.	None of these
Answer» D. None of these

Discussion

27.	A lorry and a car moving with the same kinetic energy are brought to rest by applying the same retarding force. Then:
A.	lorry will come to rest in a shorter distance
B.	car will come to rest in a shorter distance
C.	in order to know which one will come to rest in a shorter distance, one needs to know the masses of the lorry and the car
D.	both come to rest in same distance
Answer» E.

Discussion

28.	A body of mass m1 moving with an unknown velocity of \({v_1}\hat i\;\), undergoes a collinear collision with a body of mass m2 moving with velocity \({v_2}\hat i\). After the collision, m1 and m2 move with velocities of \({v_3}\hat i\;{\rm{and}}\;{v_4}\hat i\) respectively. If m2 = 0.5m1 and v3 = 0.5v1, then v1 is:
A.	\({{\rm{v}}_4} - \frac{{{{\rm{v}}_2}}}{2}\)
B.	v4 – v2
C.	\({{\rm{v}}_4} - \frac{{{{\rm{v}}_2}}}{4}\)
D.	v4 + v2
Answer» C. \({{\rm{v}}_4} - \frac{{{{\rm{v}}_2}}}{4}\)

Discussion

29.	A magnet of total magnetic moment \({10^{ - 2}}\hat i\) A-m2 is placed in a time varying magnetic field, \(B\hat i\left( {\cos \omega t} \right)\), where B = 1 T and ω = 0.125 rad/s. The work done for reversing the direction of the magnetic moment at t = 1s is
A.	0.01 J
B.	0.007 J
C.	0.014 J
D.	0.028 J
Answer» D. 0.028 J

Discussion

30.	On body work is done only when: _____.
A.	Forces act on it.
B.	It provides energy boost through a mechanical effect.
C.	Displacement takes place there.
D.	It moves through a certain distance.
Answer» D. It moves through a certain distance.

Discussion

31.	A construction worker holds a heavy tool box. How much work is done by the worker?
A.	FGd
B.	mgh
C.	½ mv2
D.	zero
Answer» E.

Discussion

32.	Given the current i(t) and voltage v(t) of a circuit element, the power p(t) and energy w(t) are given by:
A.	p(t) = v(t).i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t i\left( \tau \right)d\tau \)
B.	p(t) = v(t).i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t p\left( \tau \right)d\tau \)
C.	p(t) = v(t).i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t v\left( \tau \right)d\tau \)
D.	p(t) = v(t) + i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t p\left( \tau \right)d\tau \)
Answer» C. p(t) = v(t).i(t) and \(w\left( t \right) = \mathop \smallint \nolimits_0^t v\left( \tau \right)d\tau \)

Discussion

33.	1 Joule = ______
A.	1 N × 1 cm
B.	1 Pa × 1 m
C.	1 W × 1 m
D.	1 N × 1 m
Answer» E.

Discussion

34.	A particle moves in one dimension from rest under the influence of a force that varies with the distance travelled by the particle as shown in the figure. The kinetic energy of the particle after it has travelled 3 m is:
A.	4 J
B.	2.5 J
C.	6.5 J
D.	5 J
Answer» D. 5 J

Discussion

35.	A force 20 N displaces an object through 2 m and does a work of 20 J. The angle between the force and displacement is:
A.	90°
B.	0°
C.	30°
D.	60°
Answer» E.

Discussion

36.	A uniform cable of mass 'M' and length ‘L’ is placed on a horizontal surface such that its \({\left( {\frac{1}{n}} \right)^{th}}\) part is hanging below the edge of the surface. To lift the hanging part of the cable upto the surface, the work done should be:
A.	\(\frac{{MgL}}{{2{n^2}}}\)
B.	\(\frac{{MgL}}{{{n^2}}}\)
C.	\(\frac{{2MgL}}{{{n^2}}}\)
D.	\(nMgL\)
Answer» B. \(\frac{{MgL}}{{{n^2}}}\)

Discussion

37.	A weightlifter holds a body of 100 kg on his shoulders for two minutes. The work done by him is :
A.	Zero
B.	1000 J
C.	10 J
D.	1 J
Answer» B. 1000 J

Discussion

38.	1 horse power is equal to approximately ______ watts.
A.	500
B.	750
C.	1000
D.	250
Answer» C. 1000

Discussion

39.	An object of 20 kg mass moves with a speed of 5 ms-1, its kinetic energy will be ______.
A.	250 Pa
B.	250 N
C.	250 kg
D.	250 J
Answer» E.

Discussion

40.	A ball falls from a height of a 20 m, and then bounces back up to 10 m height. The loss of energy is
A.	5%
B.	25%
C.	50%
D.	75%
Answer» D. 75%

Discussion

41.	In which case, positive work is done with least resistance?
A.	While there is electric current in a conductor
B.	While a ball is rolling on a horizontal levelled floor
C.	While a ripe fruit is falling from a tree
D.	While a helicopter is rising up from the ground
Answer» D. While a helicopter is rising up from the ground

Discussion

42.	An object of mass m is raised to a height 4h above ground level. Find the potential energy of the object.
A.	8 mgh
B.	¼ mgh
C.	4 mgh
D.	0.4 mgh
Answer» D. 0.4 mgh

Discussion

43.	A spring whose upstretched length is l has a force constant k. The spring is cut into two pieces of upstretched lengths l1 and l2 where, l1 = nl2 and n is an integer. The ratio k1/k2 of the corresponding force constants- k1 and k2 will be:
A.	n
B.	\(\frac{1}{{{{\rm{n}}^2}}}\)
C.	\(\frac{1}{{\rm{n}}}\)
D.	n2
Answer» D. n2

Discussion

44.	Momentum of a particle of mass m is p. Its kinetic energy will be
A.	p2m
B.	p2 / m
C.	mp
D.	p2 / 2m
Answer» E.

Discussion

45.	If a pump can raise 1000 litres of water per minute to a height of 45 metres, then the horsepower of the pump is
A.	9 HP
B.	10 HP
C.	24.3 HP
D.	None of these
Answer» C. 24.3 HP

Discussion

46.	For the given cyclic process CAB as shown for a gas, the work done is
A.	5 J
B.	10 J
C.	1 J
D.	30 J
Answer» C. 1 J

Discussion

47.	In a barrage of 300000 m2 area with a tide height of 3 m, barrage drain time of 10 hr, density of seawater as 1025 kg/m3 and gravitational acceleration as 9.8 m/s2, the average power will be
A.	377 kW
B.	381 kW
C.	388 kW
D.	396 kW
Answer» B. 381 kW

Discussion

48.	Identify the correct statement from among the following
A.	Work and kinetic energy do not have the same unit
B.	Work = Energy x Power
C.	Work is equal to power per unit time.
D.	Work and potential energy have the same unit
Answer» E.

Discussion

49.	A rod of length 50 cm is pivoted at one end. It is raised such that if makes an angle of 30° from the horizontal as shown and released from rest. Its angular speed when it passes through the horizontal (in rad s-1) will be (g = 10 ms-2)
A.	\(\sqrt {\frac{{30}}{2}} \)
B.	\(\sqrt {30} \)
C.	\(\frac{{\sqrt {20} }}{3}\)
D.	\(\frac{{\sqrt {30} }}{2}\)
Answer» C. \(\frac{{\sqrt {20} }}{3}\)

Discussion

50.	A bullet of 10 g mass comes out with an initial velocity of 1000 m/s and strikes the earth at a velocity of 500 m/s at the same level. What will be the work done (in water) by facing resistance to air?
A.	500
B.	5000
C.	375
D.	3750
Answer» E.

Discussion

Explore topic-wise MCQs in UPSEE.

Physical quantity of _____ is measured in watt.

A pump is required to lift 600 kg of water per minute from a well 25 m deep and to eject it with a speed of 50 m / s. If g = 10 m / s2, the power required to perform the above task is

A wedge of mass M = 4m lies on a frictionless plane. A particle of mass m approaches the wedge with speed v. There is no friction between the particle and the plane or between the particle and the wedge. The maximum height climbed by the particle on the wedge is given by:

Find the energy possessed by an object of mass 14 kg when it is at a height of 5 m above the ground Given g = 9.8 ms-2

Energy is the capability or ability to

A freely falling body takes 4 s to reach the ground. One second after release, the percentage of its potential energy, that is still retained is

A block of mass m is kept on a platform which starts from rest with constant acceleration \(\frac{g}{2}\) upwards as shown in figure. Work done by normal reaction on block in time t is

A positive point charge is released from rest at a distance ro from a positive line charge with uniform density. The speed (v) of the point charge, as a function of instantaneous distance r from line charge, is proportional to:

A man of 25 kg weight climbs 25 stairs in 20 seconds. If the height of each stair is 40 cm, find the power (g = 10 m/s2)

If the work done is zero, then the angle between the force and displacement is:

If two objects, whose masses are 'm' and '9m', are moving with equal kinetic energy, find the ratio of their linear momentum.

A 2 mW laser operates at a wavelength of 500 nm. The number of photons that will be emitted per second is:[Given Planck’s constant h = 6.6 × 10-34 Js, speed of light c = 3.0 × 108 6m/s]

A body is thrown vertically upwards. During its rise the potential energy _______ and the kinetic energy _______.

An α-particle of mass m suffers one-dimensional elastic collision with a nucleus at rest of unknown mass. It is scattered directly backwards losing 64% of its initial kinetic energy. The mass of the nucleus is

5.5 kwh = ?

An object of mass 1 Kg is moving a velocity 10 m/s. Find the kinetic energy of the object.

An electric iron of resistance 20 ohm takes a current of 5 A. The heat flow in 30 s is:

A particle starts from the origin at time t = 0 and moves along the positive X -axis. The graph of velocity with respect to time is shown in figure. What is the position of the particle at time t = 5s?

By applying the brakes without causing a skid, the driver of a car is able to stop within a distance of 5m, if it is going at 36 kmph. If the car were going at 72 kmph, using the same brakes, he can stop the car over a distance of:

A particle ‘P’ is formed due to a completely inelastic collision of particles ‘x’ and ‘y’ having de-Broglie wavelengths ‘λx’ and ‘λy’ respectively. If x and y were moving in opposite directions, then the de-Broglie wavelength of ‘P’ is:

A shaft shown in the figure rotates at a rate of 100 rev/min against a constant torque of 1000 N-m. The power required to rotate the shaft is

A body of mass 200g moves with the velocity of 20 m / s. The kinetic energy will be ___________?

Mechanical energy is equal to:

A machine does 20 Joules of work in 5 seconds. Its power is:

A lorry and a car moving with the same kinetic energy are brought to rest by applying the same retarding force. Then:

A magnet of total magnetic moment \({10^{ - 2}}\hat i\) A-m2 is placed in a time varying magnetic field, \(B\hat i\left( {\cos \omega t} \right)\), where B = 1 T and ω = 0.125 rad/s. The work done for reversing the direction of the magnetic moment at t = 1s is

On body work is done only when: _____.

A construction worker holds a heavy tool box. How much work is done by the worker?

Given the current i(t) and voltage v(t) of a circuit element, the power p(t) and energy w(t) are given by:

1 Joule = ______

A particle moves in one dimension from rest under the influence of a force that varies with the distance travelled by the particle as shown in the figure. The kinetic energy of the particle after it has travelled 3 m is:

A force 20 N displaces an object through 2 m and does a work of 20 J. The angle between the force and displacement is:

A uniform cable of mass 'M' and length ‘L’ is placed on a horizontal surface such that its \({\left( {\frac{1}{n}} \right)^{th}}\) part is hanging below the edge of the surface. To lift the hanging part of the cable upto the surface, the work done should be:

A weightlifter holds a body of 100 kg on his shoulders for two minutes. The work done by him is :

1 horse power is equal to approximately ______ watts.

An object of 20 kg mass moves with a speed of 5 ms-1, its kinetic energy will be ______.

A ball falls from a height of a 20 m, and then bounces back up to 10 m height. The loss of energy is

In which case, positive work is done with least resistance?

An object of mass m is raised to a height 4h above ground level. Find the potential energy of the object.

A spring whose upstretched length is l has a force constant k. The spring is cut into two pieces of upstretched lengths l1 and l2 where, l1 = nl2 and n is an integer. The ratio k1/k2 of the corresponding force constants- k1 and k2 will be:

Momentum of a particle of mass m is p. Its kinetic energy will be

If a pump can raise 1000 litres of water per minute to a height of 45 metres, then the horsepower of the pump is

For the given cyclic process CAB as shown for a gas, the work done is

In a barrage of 300000 m2 area with a tide height of 3 m, barrage drain time of 10 hr, density of seawater as 1025 kg/m3 and gravitational acceleration as 9.8 m/s2, the average power will be

Identify the correct statement from among the following

A rod of length 50 cm is pivoted at one end. It is raised such that if makes an angle of 30° from the horizontal as shown and released from rest. Its angular speed when it passes through the horizontal (in rad s-1) will be (g = 10 ms-2)

A bullet of 10 g mass comes out with an initial velocity of 1000 m/s and strikes the earth at a velocity of 500 m/s at the same level. What will be the work done (in water) by facing resistance to air?

A body is thrown vertically upwards. During its rise the potential energy _ and the kinetic energy _.