Simple Machines - Jamb Physics Past Questions and Answers

Question 6:

• 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 7:

• JAMB 1984

A plane inclined at an angle of 30^o to the horizontal has an efficiency of 60%. The force parallel to the plane required to push a load of 120N uniformly up the plane is

A. 60N
B. 100N
C. 120N
D. 200N
E. 240N

Question 8:

• 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

Question 9:

• JAMB 1987

The mechanical advantage(MA) of an inclined plane depends on

A. Its length
B. Its height
C. The product of its length and height
D. The ratio of its length to its height

Question 10:

• JAMB 1989

A block-and-tackle system is used to lift a load of 20N through a vertical height of 10m. if the efficiency of the system is 40%, how much work is done against friction?

A. 80J
B. 120J
C. 300J
D. 500J