EASY

Earn 100

The distance between the forces acting in the couple is-

50% studentsanswered this correctly

Important Questions on Work, Energy and Power

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

Define couple. State the SI unit of moment of couple.

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

The work done on a particle of mass

m

by a force

K [\frac{x}{{(x^{2} + y^{2})}^{3 / 2}} \hat{i} + \frac{y}{{(x^{2} + y^{2})}^{3 / 2}} \hat{j}]

(

K

being a constant of appropriate dimensions, when the particle is taken from the point

(a, 0)

to the point

(0, a)

along a circular path of radius

a

about the origin in the x-y plane is

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

Consider a force

\vec{F} = - x \hat{i} + y \hat{j}

. The work done by this force in moving a particle from point

A (1,0)

B (0,1)

along the line segment is : (all quantities are in SI units)

Question Image

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

A mass $m$ is supported by a massless string wound around a uniform hollow cylinder of mass $m$ and radius $R$ . If the string does not slip on the cylinder, then with what acceleration will the mass release? (Assume $g =$ acceleration due to gravity)

Question Image

HARD

Physics>Mechanics>Work, Energy and Power>Work

A force

(F) = - 5 \hat{i} - 7 \hat{j} + 3 \hat{k}

acting on a particle causes a displacement

(s) = 3 \hat{i} + 2 \hat{j} + a \hat{k}

in its own direction. If the work done is

14 J

, then the value of

a

is:

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

A square loop of side

2 a

and carrying current

I

is kept in

xz

plane with its centre at origin. A long wire carrying the same current

I

is placed parallel to

z

-axis and passing through point

(0, b, 0), (b > > a)

. The magnitude of torque on the loop about

z

-axis will be :

EASY

Physics>Mechanics>Work, Energy and Power>Work

What do you understand by the clockwise and anticlockwise moment of force? When is it taken positive?

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

A force of

20 N

acts on a wheel of

50 cm

tangentially. What is the torque acting on wheel ?

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

A body is acted upon by two forces each of magnitude

F

but in opposite direction. State the effect of the forces if the two forces act at two different points of the body at a separation

r

EASY

Physics>Mechanics>Work, Energy and Power>Work

State the SI unit of moment of couple?

EASY

Physics>Mechanics>Work, Energy and Power>Work

Two equal and opposite force act on a rigid body at a certain distance. Then

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

It is easier to turn the steering wheel of a large diameter than that of a small diameter. Give reason.

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

What are the factors on which torque depends?

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

A uniform metre rule placed on a fulcrum at its middle point $O$ and having a weight $40 g f$ at $10 c m$ mark and a weight of $20 g f$ at the $90 c m$ mark, Is the metre rule in equilibrium? If not how will the rule turn?

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

When does a body rotate? State one way to change the direction of rotation of the body. Give a suitable example to explain your answer.

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

Two forces each of magnitude

2 N

act vertically upwards and downwards respectively on the two ends of a uniform rod of length

1 m

freely pivoted at its centre. Determine the resultant moment of the force about the mid-point of the rod.

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

What do you understand by the turn couple? State its effect. Illustrate its action by giving two examples.

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

What do you understand by the term couple? State its effect. Give two examples of couple action in our daily life.

MEDIUM

Physics>Mechanics>Work, Energy and Power>Work

Define: (i) C.G, (ii) Moment of force and (iii) Degradation of energy.

EASY

Physics>Mechanics>Work, Energy and Power>Work

A rigid rod of length

2 L

is acted upon by some forces. All forces labelled

F

have the same magnitude. Which cases have a non-zero net torque acting on the rod about its center?
Question Image

The distance between the forces acting in the couple is-

Important Questions on Work, Energy and Power

Learn and Prepare for any exam you want !