EASY

Earn 100

Which of the following energy travels in the form of an electromagnetic wave?

50% studentsanswered this correctly

Important Questions on Energy

HARD

Physics>Change>Energy>Forms of Energy

A body is thrown from the surface of the earth with velocity

u m s^{- 1}

. The maximum height in meters above the surface of the earth up to which it will reach is (where,

R =

radius of earth,

g =

acceleration due to gravity),

EASY

Physics>Change>Energy>Forms of Energy

Two springs

A

and

B

(k_{A} = 2 k_{B})

are stretched by applying forces of equal magnitudes at the four ends. If the energy stored in

A

E

, then that in

B

EASY

Physics>Change>Energy>Forms of Energy

When a long spring is stretched by

2 cm

, its potential energy is

U

. If the spring is stretched by

10 cm

, the potential energy stored in it will be

HARD

Physics>Change>Energy>Forms of Energy

Two particles of mass

m

and

M

are initially at rest at infinite distance. Find their relative velocity of approach due to gravitational attraction, when

d

is their separation at any instant

EASY

Physics>Change>Energy>Forms of Energy

A person brings a mass of

1 kg

from infinity to a point

A

. Initially, the mass was at rest but it moves at a speed of

2 m s^{- 1}

as it reached

A

. The work done by the person on the mass is

- 3 J

. The potential at

A

HARD

Physics>Change>Energy>Forms of Energy

Three identical stars, each of mass

M,

form an equilateral triangle (stars are positioned at the corners) that rotates around the centre of the triangle. The system is isolated and the edge length of the triangle is

L .

The amount of work done, that is required to dismantle the system is

MEDIUM

Physics>Change>Energy>Forms of Energy

When mass and speed are doubled the

K . E .

increases

MEDIUM

Physics>Change>Energy>Forms of Energy

When mass and speed are doubled the

K . E .

increases

EASY

Physics>Change>Energy>Forms of Energy

Heat is a form of _____.

MEDIUM

Physics>Change>Energy>Forms of Energy

Two springs have their force constant

k_{1}

and

k_{2} (k_{1} > k_{2})

. When they are stretched with the same force,

EASY

Physics>Change>Energy>Forms of Energy

Four equal masses (each of mass

M

) are placed at the corners of a square of side

a

. The escape velocity of a body from the centre

O

of the square is

EASY

Physics>Change>Energy>Forms of Energy

Two identical thin rings each of radius

R

are coaxially placed at a distance

R

. If the rings have a uniform mass distribution and each has mass

m_{1}

and

m_{2}

respectively, then the work done in moving a mass

m

from centre of one ring to that of the other is

EASY

Physics>Change>Energy>Forms of Energy

A body of mass

m kg

starts falling from a point

2 R

above the Earth's surface. Its kinetic energy when it has fallen to a point

R

above the Earth's surface is [

R -

Radius of Earth,

M —

Mass of Earth,

G —

Gravitational Constant]

EASY

Physics>Change>Energy>Forms of Energy

If two springs

A

and

B

with spring constants

2 k

and

k

, are stretched separately by same suspended weight, then the ratio between the work done in stretching

A

and

B

EASY

Physics>Change>Energy>Forms of Energy

Which type of energy is produced by the movement of electric charges?

MEDIUM

Physics>Change>Energy>Forms of Energy

Two equal masses are attached to the two ends of a spring of spring constant

k

. The masses are pulled out symmetrically to stretch the spring by a length

x

over its natural length. The work done by the spring on each mass is

HARD

Physics>Change>Energy>Forms of Energy

The radius and mass of earth are increased by

0.5 % .

Which of the following statements are true at the surface of the earth?

EASY

Physics>Change>Energy>Forms of Energy

A ball is thrown up vertically in air. As it rises there is an increase in its

EASY

Physics>Change>Energy>Forms of Energy

The gravitational potential energy of a body of mass

m

at the Earth's surface is,

- m g R_{e}

. Its gravitational potential energy at a height

R_{e}

from the Earth's surface will be (Here

R_{e}

is the radius of the earth)

EASY

Physics>Change>Energy>Forms of Energy

A point

P (R \sqrt{3}, 0, 0)

lies on the axis of a ring of mass

M

and radius

R

. The ring is located in

y - z

plane with its centre at origin

O

. A small particle of mass

m

starts from

P

and reaches

O

under gravitational attraction only. Its speed at

O

will be

Which of the following energy travels in the form of an electromagnetic wave?

Important Questions on Energy

Learn and Prepare for any exam you want !