Physics Past Questions and Answers

A machine is used to lift a load of 20 N through a height of 10 m. if the efficiency of the machine is 40%, how much work is done?

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

Question 1527:

I. Density of the liquid.<br/>II. Depth below the surface of the liquid. <br/>III. Surface area of the liquid. <br/>In which of the statement above will pressure be dependent?

A I and II only.
B II and III only.
C I, II and III only.
D I and III only.

Question 1528:

Which of the following could be effectively used to reduce friction?

A Kerosene
B Grease
C Water
D Petrol

Question 1529:

Which of the following types of waves needs a medium for propagation?

A Sound waves
B Light waves
C Radio waves
D X - rays

Question 1530:

Which of the following electromagnetic waves has the highest frequency?

A Utra - violet rays
B Radio waves
C X - rays
D Infrared - rays