(English Medium) ICSE Class 10 - CISCE Important Questions for Physics

Define couple. 

A uniform meter scale is in equilibrium as shown in the diagram : 

(i) Calculate the weight of the meter scale.
(ii) Which of the following options is correct to keep the ruler in equilibrium when 40 gf wt is shifted to 0 cm mark ?
F is shifted towards 0 cm
or
F is shifted towards 100 cm

Clockwise moment produced by a force about a fulcrum is considered to be ______.

When this triangular lamina is suspended freely from any one vertex, what is the moment of force produced by its own weight in its rest position?

The diagram shows wheel O pivoted at point A. Three equal forces F₁, F₂ and F₃ act at point B on the wheel.

1. Which force will produce maximum moment about A?
2. Give a reason for your answer in (a).

A door lock is opened by turning the lever (handle) of length 0.2 m. If the moment of force produced is 1 Nm, then the minimum force required is ______.

When a stone tied to a string is rotated in a horizontal plane, the tension in the string provides ______ force necessary for circular motion.

A non uniform beam of weight 120 N pivoted at one end is shown in the diagram below. Calculate the value of F to keep the beam in equilibrium.

A hollow ice cream cone has height 6 cm.

1. Where is the position of its center of gravity from the broad base?
2. Will its position change when it is filled completely with honey? Write Yes or No.

A moment of couple has a tendency to rotate the body in an anticlockwise direction. Then the moment of couple is taken as ______.

A metal rod AB of length 80 cm is balanced at 45 cm from the end A with 100 gf weights suspended from the two ends.

1. If this rod is cut at the centre C, then compare the weight of AC to the weight of BC.
2. Give a reason for your answer in (a).

A person standing in front of a cliff fires a gun and hears its echo after 3s. If the speed of sound in air is 336 ms^-1

1. Calculate the distance of the person from the cliff.
2. After moving a certain distance from the cliff, he fires the gun again, and this time the echo is heard 1.5 s later than the first. Calculate the distance that the person moved.

Why is a jack screw provided with a long arm?

Why is a jack screw provided with a long arm?

If the power of a motor is 100 kW, at what speed can it raise a load of 50,000 N?

A boy weighing 40 kgf climbs up a stair of 30 steps each 20 cm high in 4 minutes and a girl weighing 30 kgf does the same in 3 minutes. Compare:

1. The work done by them.
2. The power developed by them.

A stone of mass m is rotated in a circular path with a uniform speed by tying a strong string with the help of your hand. Answer the following questions

1) Is the stone moving with a uniform or variable speed?

2) Is the stone moving with a uniform acceleration? In which direction does the acceleration act?

3) What kind of force acts on the hand and state its direction?

When a body is placed on a table top, it exerts a force equal to its weight downwards on the table top but does not move or fall

1) Name the force exerted by the table top

2) What is the direction of the force?

How is work done by a force measured when the force is in the direction of displacement?