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Tuesday, 21 April 2026
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Physics Past Questions and Answers

Jamb 2007 Physics Questions

Question 31:
A blacksmith heated a metal whose cubic expansivity is 6.3 x 10-6K-1. The areal expansivity is
  • A 2.0 x 10<sup style='font-size: smaller;'>-6</sup>K<sup style='font-size: smaller;'>-1</sup>
  • B 2.1 x 10<sup style='font-size: smaller;'>-6</sup>K<sup style='font-size: smaller;'>-1</sup>
  • C 4.2 x 10<sup style='font-size: smaller;'>-6</sup>K<sup style='font-size: smaller;'>-1</sup>
  • D 6.3 x 10<sup style='font-size: smaller;'>-6</sup>K<sup style='font-size: smaller;'>-1</sup>
View Answer & Explanation
Question 32:
The ratio of the coefficient of linear expansion of two metals ∝1/∝[sub]2[/sub] is 3:4. If, when heated through the same temperature change, the ratio of the increase in length of the two metals, e1/e[sub]2[/sub] is 1:2, the ratio of the original lengths l1/l[sub]2[/sub] is
  • A <sup style='font-size: smaller;'>8</sup>/<sub style='font-size: smaller;'>3</sub>
  • B <sup style='font-size: smaller;'>3</sup>/<sub style='font-size: smaller;'>2</sub>
  • C <sup style='font-size: smaller;'>2</sup>/<sub style='font-size: smaller;'>3</sub>
  • D <sup style='font-size: smaller;'>3</sup>/<sub style='font-size: smaller;'>8</sub>
View Answer & Explanation
Question 33:
The fundamental frequency of a plucked wire under a tension of 400N is 250Hz. When the frequency is changed to 500 Hz at constant length, the tension is
  • A 1600N
  • B 400N
  • C 160N
  • D 40N
View Answer & Explanation
Question 34:
Three cells each of e.m.f 1.5 V and internal resistance 2.5Ω are connected as shown in the diagram above. Find the net e.m.f and the internal resistance
  • A 1.5V, 7.50Ω
  • B 1,5V, 0.83Ω
  • C 4.5V, 7.50Ω
  • D 4.5V, 0.83Ω
View Answer & Explanation
Question 35:
In the diagram above , if the magnetic field points into the paper and the force on a current - carrying conductor points upwards, what is the direction of the current?
  • A Upwards
  • B Downwards
  • C Right
  • D Left
View Answer & Explanation