Mechanical Advantage Velocity Ratio And Efficiency Of Machines - Physics Jamb Past Questions and Answers

Question 1 :

• JAMB 2019

If the time of flight is 96seconds, calculate the horizontal range through the point of projection.

A. 84400m
B. 69000m
C. 61440m
D. 24000m

Question 2 :

• JAMB 1979

Which of the following statements defines correctly the efficiency of a machine?

A. The load carried by the machine divided by effort required in carrying the load
B. The distance moved by the load divided by the distance moved by the effort
C. The useful work done by the machine divided by the total work put into the machine
D. The movement of the load divided by the movement of the effort about the same point
E. The temperature at the end of the application of the machine divided by the initial temperature

Question 3 :

• JAMB 1981

An inclined plane of angle \(\theta\), acting as a simple machine, has a velocity ratio

A. Sin\(\theta\)
B. \(\frac{1}{\text{sin}\theta}\)
C. Cos\(\theta\)
D. \(\frac{1}{\text{cos}\theta}\)
E. Sin\(\theta cos\theta\)

Question 4 :

• JAMB 1983

A machine has a velocity ratio of 5. It requires a 50kg weight to overcome a 200kg weight. The efficiency is

A. 4%
B. 5%
C. 40%
D. 50%
E. 80%

Question 5 :

• JAMB 1986

fig 4 represents a block-and-tackle pulley system on which an effort of W newtons supports a load of 120.0N if the efficiency of the system is 40% then the value of W is

A. 28.0N
B. 48.0N
C. 50.0N
D. 288.0N