Physics Past Questions and Answers

A herdsman yelling out to fellow herdsman heard his voice reflected by cliff 4s later. What is the velocity of sound in air if the cliff is 680m away?

A 170ms-1
B 136ms-1
C 340ms-1
D 680ms-1
E 510ms-1

Question 42:

an object 1cm high placed on the axis 15cm from a converging lens forms an image 30cm from the lens. The size of the image is

A 0.5cm
B 1.5cm
C 3cm
D 2.5m
E 2cm

Question 43:

The visible part of light consists of the following colours

A Red, indigo, infra-red, violet, yellow, green and blue
B Red, green, blue, violet, indigo, orange and yellow
C Blue, ultra-violet, infra-red, red, yellow, indigo, violet,green and orange
D Infra-red and ultra-violet
E Red, orange, yellow, green, blue, indigo and infra-red

Question 44:

An object is positioned between two plane mirrors inclined at right angles to each other. The object is 1 unit distance from each mirror, the number of images formed is

Question 45:

The angular dispersion of a prism depends on

A The index of refraction only
B The angle of incidence as well as the index of refraction
C The angle of incidence only
D The thickness of the prism
E The prism angle