Jamb Physics 2023 Past Questions and Answers

Question 61:

• JAMB 2023

The pinhole camera works on

A. The principle of the reversibility of light
B. The principle of the rectilinear propagation of light
C. Huygen’s principle
D. The principle of total internal reflection of light

Question 62:

• JAMB 2023

A step-down transformer is used on a 2.2 kV line to deliver 110 V. How many turns are on the primary windings if the secondary has 25 turns?

A. 20
B. 250
C. 200
D. 500

Question 63:

• JAMB 2023

A block of mass 0.5 kg is suspended at the 40 cm mark of a light metre rule AB that is pivoted at point E, the 90 cm mark, and is kept at equilibrium by a string attached at point D, the 60 cm mark, as shown in the figure above. Find the tension T in the string.

[Take g = \(10 ms-2\) ]

A. 16.67N
B. 15.67N
C. 14.67N
D. 18.67N

Question 64:

• JAMB 2023

A 35 kΩ is connected in series with a resistance of 40 kΩ. What resistance R must be connected in parallel with the combination so that the equivalent resistance is equal to 25 kΩ?

A. 40 kΩ
B. 37.5 kΩ
C. 45.5 kΩ
D. 30 kΩ

Question 65:

• JAMB 2023

A piano wire 50 cm long has a total mass of 10 g and its stretched with a tension of 800 N. Find the frequency of the wire when it sounds its third overtone note.

A. 800 Hz
B. 600 Hz
C. 400 Hz
D. 200 Hz