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Wednesday, 28 October 2026
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Physics Past Questions and Answers

Jamb 1994 Physics Questions

Question 21:
The sound from a source travelled to the bottom of the sea and the echo was heard 4s later. If the speed of sound in sea water is 1500ms-1 the depth of the sea is
  • A 6000m
  • B 3000m
  • C 1500m
  • D 375m
View Answer & Explanation
Question 22:
The fundamental frequency of vibration of a sonometer wire may be halved by
  • A Doubling the length of the wire
  • B Doubling the mass of the wire
  • C Reducing the tension by half
  • D Reducing the absolute temperature by half
View Answer & Explanation
Question 23:
A pipe of length 45cm is closed at the end. Calculate the fundamental frequency of the sound wave generated in the pipe if the velocity of sound in air is 360ms-1 [Neglect end correction]
  • A 5.5Hz
  • B 148.5Hz
  • C 200.0Hz
  • D 550.0Hz
View Answer & Explanation
Question 24:
The note produced by a stretched string has a fundamental frequency of 400Hz. If the length of the string is doubled while the tension in the string is increased by a factor of 4, the frequency is
  • A 200Hz
  • B 400Hz
  • C 800Hz
  • D 1600Hz
View Answer & Explanation
Question 25:
To produce a parallel beam of light from a concave mirror, the distance at a which the lamp should be placed from the mirror is equal to
  • A The focal length
  • B Two times the focal length
  • C The distance of the image
  • D Two times the radius of curvature
View Answer & Explanation