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

The figure below shows a simple pendulum of mass 200 g. It is displaced from the mean position A to the extreme position B. The potential energy at the position A is zero. At the position B the pendulum bob is raised by 5 m.

1. What is the potential energy of the pendulum at the position B?
2. What is the total mechanical energy at point C?
3. What is the speed of the bob at the position A when released from position B?
   (Take g = 10 ms^-2, given that there is no loss of energy.)

Which class of lever will always have MA > 1 and why?

A boy uses a single fixed pulley to lift a load of 50 kgf to some height. Another boy uses a single movable pulley to lift the same load to the same height. Compare the effort applied by them. Give a reason to support your answer.

A pulley system with VR = 4 is used to lift a load of 175 kgf through a vertical height of 15 m. The effort required is 50 kgf in the downward direction. (g = 10 N kg^-1)

Calculate:

1. Distance moved by the effort
2. Work done by the effort
3. M.A. of the pulley system
4. Efficiency of the pulley system

With reference to the terms mechanical advantage, velocity ratio and efficiency of a machine, name and define the term that will not change for the machine of a given design.

From the diagram given below. answer the question that follows:

1. What kind of pulleys are A and B?
2. State the purpose of pulley B.
3. What effort has to be applied at C just raise the load L = 20 kgf?
   (Neglect the weight of pulley A and friction)

A pulley system has three pulleys. A load of 120 N is overcome by applying an effort of 50 N. Calculate the Mechanical Advantage and Efficiency of this system.

A scissor is a ______ multiplier.

A block and tackle system has V.R. = 5.

Draw a neat labeled diagram of a system indicating the direction of its load and effort.

A block and tackle system has V.R. = 5.

Rohan exerts a pull of 150 kgf. What is the maximum load he can raise with this pulley system if its efficiency = 75%?

What is the principle of an ideal machine?

Two forces each of 5N act vertically upwards and downwards respectively on the two ends of a uniform metre rule which is placed at its mid-point as shown in the diagram. Determine the magnitude of the resultant moment of these forces about the midpoint.

Draw a diagram to show how a single pulley can be used so as to have its ideal M.A= 2.

The diagram below shows a lever in use:

1. To which class of levers does it belong?
2. Without changing the dimensions of the lever, if the load is shifted towards the fulcrum what happens to the mechanical advantage of the lever?

Draw a diagram of a block and tackle system of pulleys having a velocity ratio of 5. In your diagram indicate clearly the points of application and the directions of the load L and effort E. Also mark the tension T in each strand.

The pulley system has drawn lifts a load of 150 N when an effort of 60 N is applied. Find its mechanical advantage.

Is the above pulley system an ideal machine or not?

The diagram below shows a claw hammer used to remove a nail : 

(i) To which class of lever does it belong ?
(ii) Give one more example of the same class of lever mentioned by you in (i) for which the mechanical advantage is greater than one.

The diagram below shows a pulley arrangement : 

(i) Copy the diagram and mark the direction of tension on each strand of the string.
(ii) What is the velocity ratio of the arrangement ?
(iii) If the tension acting on the string is T, then what is the relationship between T and effort E ?
(iv) If the free end of the string moves through distance x, find the distance by which the load is raised.

The following belong to which class of lever?

A pair of scissors