The range of voltmeter is 10V and its internal resistance is 50Ω.

⇦

⇨

The range of voltmeter is 10V and its internal resistance is 50Ω. To convert it to a voltmeter of range 15V, how much resistance is to be added?

Options

(a) Add 25Ω resistor is parallel
(b) Add 25Ω resistor is series
(c) Add 125Ω resistor in parallel
(d) Add 125Ω resistor in series

Correct Answer:

Add 25Ω resistor is series

Explanation:

The current in case of voltmeter range 10 V and resistance 50 Ω is I = 10 / 50 —–(i)

Let X is the resistance conneced in order to make a voltmeter with range 15 V is I = 15 / X —-(ii)

Equating equation (i) and (ii), we get

15 / X = 10 / 50 ⇒ X = (15 × 50) = 75 Ω

Then, R = 75 – 50 = 25 Ω must be connected in series, because V ∝ R when current is constant.

Related Questions:

1. An electric dipole of dipole moment p is placed in a uniform external electric field
2. If the rise in height of capillary of two tubes is 6.6 cm and 2.2 cm
3. A particle starts its motion from rest under the action of a constant force
4. A force F=ai+3j+6k is acting at a point r=2i-6j-12k. The value of α for
5. Two sources of sound placed close to each other are emitting progressive waves

Topics: Current Electricity (136)
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.

---

Share this page with your friends