Machine

Q.

Define a simple machine. Give examples.

Q.

A staircase is an example of

1. Lever

2. Wheel and axle

3. Inclined plane

4. Wedge

Q.

The handle of a nutcracker is 16cm long and a nut is placed 2cm from its hinge. If a force of 4kgf is applied at the end of the handle to crack it, what weight if simply, placed on the nut will crack it.

Q. What does the magnitude of a force represents?

1. Change in force
2. Type of force
3. Direction of force
4. Strength of force

Q.

Which principle of work is applied to a machine?

1. For an ideal machine, the work done by the machine is never equal to the work done on it.

2. For an ideal machine, the work done by the machine is always equal to the work done on it.

3. For an ideal machine, the work done by the machine is always greater to the work done on it.

4. For an ideal machine, the work done by the machine is always less to the work done on it.

Q.

Can a machine change the speed? If yes, give an example.

Q.

An object is at rest. A force cannot move it but changes its shape and size and shape. What is the type of force?

Q. Which of the following does NOT require a force?

1. Rowing of a boat
2. Catching a moving cricket ball
3. sitting ideal
4. Bursting of a balloon filled with lots of air

Q.

Can every force produce motion in every object?

Q.

A crane lifts a block of mass 400 kg through a vertical height of 40 m. If acceleration due to gravity is 9.8 m/s², calculate the work done by the crane.

Q.

A load of $220kg$ is vertically pulled up by a crane through a vertical height of $16m$ in $40s$. Calculate the force acting in the upward direction.

[Take g=$9.8\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$s^2$}\right.$]

Q.

A lever work on the principle of

1. Moments

2. Gravitation

3. Momentum

4. None of these

Q.

Differentiate between the following.

Pulley and wheel and axle

Q.

Pick out the one from the options which is responsible for changing the point of application of force.

1. Wheel

2. Wedge

3. Screw

4. Scissors

Q.

How are simple machines helpful in achieving a specific purpose?

Q. A force is a _ _ _ _ _ _ _ _ _ _ _ quantity and has_ _ _ _ _ _ _ .
A. scalar, magnitude and direction
B. vector, magnitude and direction.
C.​scalar, magnitude only.
D.vector, direction only.

Q. What action is being applied by the character on the rope shown below while hanging upside down?

1. Both push and pull
2. Pull
3. Neither push nor pull
4. Push

Q.

Which of the following ways depict the usefulness of a machine?

1. In lifting heavy load by using less effort.

2. Loss in speed.

3. Changing the direction of effort.

4. Both A and C

Q. A body is exerting a force of 10 N on a table. The table will exert a force of on the body.

1. $12\text{N}$
2. $10\text{N}$
3. $8\text{N}$

Q. A body is exerting a force of 10 N on a table. The table will exert a force of on the body.

1. $10\text{N}$
2. $8\text{N}$
3. $12\text{N}$