Physics 1990 Jamb Past Questions and Answers

Question 21 :

• JAMB 1990

An object which is 3cm high is placed vertically 10cm in front of a concave mirror. If this object produces an image 40cm from the mirror, the height of the image is

A. 0.75cm
B. 4.00cm
C. 8.00cm
D. 12.00cm

Question 22 :

• JAMB 1990

A boy looks at the image of an object in a plane mirror. He observes two images, a main bright one and the other faint. The observed images result from

A. Reflection only
B. Refraction only
C. Diffraction and interference
D. Reflection and refraction
E. Reflection and diffraction

Question 23 :

• JAMB 1990

What must be the distance between an object and a converging lens of focal length 20cm to produce an erect image two times the object height?

A. 20cm
B. 15cm
C. 10cm
D. 5cm

Question 24 :

• JAMB 1990

For a short sighted person, light rays from a point on a very distant object is focused

A. In front of the retina
B. On the retina by a converging lens
C. Behind the retina by a diverging lens
D. In front of the retina, a distance 2F from the lens

Question 25 :

• JAMB 1990

When light is incident on an object which is magenta in colour, which of the following colour would be absorbed?

A. Red and blue
B. Green only
C. Red and green
D. Red only