A 40-W instrument has a resistance of 90\(\Omega\). On what voltage should it be operated…

Physics JAMB 1993

A 40-W instrument has a resistance of 90\(\Omega\). On what voltage should it be operated normally?

  • 60V checkmark
  • 150V
  • 225V
  • 3600V

The correct answer is: A

Explanation

P = \(\frac{V}{R}\)

V = \(\sqrt{PR}\)

V = \(\sqrt{40 \times 90}\)

= 60V
Previous Question Next Question

Leave A Comment