A galvanometer of resistance 50Ω is connected to a battery of 3 V along with a resistance

A Galvanometer Of Resistance 50 Is Connected To A Battery Physics Question

A galvanometer of resistance 50Ω is connected to a battery of 3 V along with a resistance of 2950 Ω in series. A full scale deflection of 30 divisions is obtained in the galvanometer. In order to reduce this deflection to 20 divisions, the resistance in series should be

Options

(a) 6050 Ω
(b) 4450 Ω
(c) 5050 Ω
(d) 5550 Ω

Correct Answer:

4450 Ω

Explanation:

I=3 / (50+2950) = 10⁻³ A

Current for 30 divisions=10⁻³ A

Current for 20 divisions=10⁻³ * 20/30

=2*10⁻³ / 3 Amperes

For the same deflection to obtain for 20 divisions let resistance added be R, therefore,

2*10⁻³ / 3 = 3 / (50+R)

(50+R) = 9 *10⁻³ / 2

(50+R) = 4500

Therefore R=4450Ω

Related Questions:

  1. The value of Planck’s constant is
  2. A sphere of 4cm radius is suspended with in a hollow sphere of 6cm radius. If the inner
  3. The escape velocity of a body from earth’s surface is Ve. The escape velocity
  4. A potentiometer wire has length 4m resistance 8Ω. The resistance that must be connected
  5. The velocity of a particle at an instant is 10 ms⁻¹.After 3 s its velocity will become

Topics: Alternating Current (96)
Subject: Physics (2479)

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

NEETLab Mobile App

Share this page with your friends

Be the first to comment

Leave a Reply

Your email address will not be published.


*