Jamb Physics 2019 Past Questions and Answers

Question 21:

• JAMB 2019

Ripple in a power supply unit is caused by

A. Using an alternating current source
B. Forward voltage drop
C. Heavy load
D. Using a zener diode

Question 22:

• JAMB 2019

When th temperature of a liquid is increased, its surface tension

A. Increases
B. Decreases
C. Remain constant
D. Increases then decreases

Question 23:

• JAMB 2019

The distance between an object and its real image in a convex lens is 40cm. If the magnification of the image is 3, calculate the focal length of the lens

A. 6.5 cm
B. 7.5 cm
C. 8.5 cm
D. 4.5 cm

Question 24:

• JAMB 2019

A ray of light passes through the centre of curvature of a concave mirror and strikes the mirror. At what angle is the ray reflected?

A. 180\(^o\)
B. 90\(^o\)
C. 0\(^o\)
D. 60\(^o\)

Question 25:

• JAMB 2019

The pin-hole camera produces a less sharply defined image when the

A. Pin-hole is larger
B. Illumination is less
C. Screen is further from the pin-hole
D. Object is further from the pin-hole