Worksheet: Machines | Physics Class 10 ICSE PDF Download

A. Multiple Choice Questions

Q1. Which quantity tells how many times a machine multiplies the effort force?

(a) Velocity Ratio

(b) Mechanical Advantage

(c) Efficiency

(d) Work Output

Q2. Velocity Ratio (VR) of a machine is defined as:

(a) Load ÷ Effort

(b) Work Output ÷ Work Input

(c) Displacement of effort ÷ Displacement of load

(d) Effort ÷ Load

Q3. An ideal machine has efficiency equal to:

(a) 0%

(b) 50%

(c) 75%

(d) 100%

Q4. In which class of lever is the effort between the fulcrum and the load?

(a) Class I

(b) Class II

(c) Class III

(d) None of these

Q5. A single movable pulley (ideal) is used to lift a 100 N load. The effort required is:

(a) 100 N

(b) 75 N

(c) 50 N

(d) 25 N

B. Short Answer Questions

Q6. A lever has an effort arm of 60 centimetres and a load arm of 20 centimetres. Find the Mechanical Advantage and say whether it is a force multiplier.

Q7. A machine lifts a 240 newton load by applying an effort of 80 newton. If its Velocity Ratio is 4, find (a) the Mechanical Advantage, (b) the efficiency.

Q8. What does a single fixed pulley do? State its Mechanical Advantage, Velocity Ratio and its main use.

Q9. Identify the class of lever when the load lies between the fulcrum and the effort. Give two examples and state whether its Mechanical Advantage is greater than 1 or less than 1.

Q10. A block-and-tackle system has 4 strands of rope supporting the load (ideal). If the load is 200 newton, find (a) the Mechanical Advantage and the Velocity Ratio, (b) the effort needed, (c) how far the effort moves when the load rises by 0.5 metre.

C. Long Answer Questions

Q11. A machine lifts a 300 newton load through 2 metres while the effort point moves 6 metres. The effort used is 120 newton. Find (a) the Mechanical Advantage, (b) the Velocity Ratio, (c) the efficiency, (d) the work input and work output.

Q12.A wheelbarrow acts as a Class II lever. The distance from fulcrum (the wheel) to the load is 25 centimetres, and from fulcrum to the effort (handles) is 75 centimetres. The load is 180 newton.
 Find (a) the Mechanical Advantage, 
(b) the effort needed, 
(c) state whether this lever is a force multiplier and why.

Q13. A single movable pulley is combined with a single fixed pulley so that you can pull down to lift the load up. The system is ideal. A 360 newton load is to be raised by 1.5 metres. Find (a) the effort required, (b) how far the free end of the rope must be pulled, (c) comment on force gain and speed relation.