Jamb Physics 2021 Past Questions and Answers

Question 1:

• JAMB 2021

A 2H inductor has negligible resistance and is connected to a \(\frac{50}{\pi}\) Hz A.C supply. The reactance of the inductor is?

A. 200\(\Omega\)
B. 50\(\Omega\)
C. \(\frac{100}{\pi}\)
D. \(\frac{25}{\pi \Omega}\)

Question 2:

• JAMB 2021

An astronomical telescope is said to be in normal adjustment when the?

A. Eye is accommodated
B. Focal length of an object lens is longer than that of eye piece
C. Final image is at the near point of eye
D. Final image is at infinity

Question 3:

• JAMB 2021

The velocities of light in air and glass are 3.0 x 10\(^8\)ms\(^{-1}\) and 2.0 x 10\(^8\)ms\(^{-1}\) respectively. If the angle of refraction is 30º, the sine of the angle of incidence is?

A. 0.33
B. 0.50
C. 0.67
D. 0.75

Question 4:

• JAMB 2021

The inside portion of part of a hollow metal sphere of diameter 20cm is polished. The portion will therefore form a?

A. Concave mirror of focal length 5cm
B. Concave mirror of focal length 10cm
C. Convex mirror of focal length 5cm
D. Convex mirror of focal length 10cm

Question 5:

• JAMB 2021

A man stands 4m in front of a plane mirror. If the mirror is moved 1m towards the man, the distance between him and his new image is?

A. 3m
B. 5m
C. 6m
D. 10m