A gramophone record is revolving with an angular velocity ?. A coin is placed at

⇦

⇨

A gramophone record is revolving with an angular velocity ?. A coin is placed at a distance r from the centre of the record. The static coefficient of friction is µ. The coin will resolve with the record if:

Options

(a) r = µ g ?ￂﾲ
(b) r < ?ￂﾲ / µ g
(c) r <= µ g / ?ￂﾲ
(d) r >= µ g / ?ￂﾲ

Correct Answer:

r <= µ g / ?ￂﾲ

Explanation:

For the coin to revolve with the record, centrifugal force <= frictional force mr ?ￂﾲ <= µ mg r <= µg / ?ￂﾲ

Related Questions:

1. A solenoid of length l metre has self inductance L henry. If number of turns
2. What is the wavelength of light for the least energetic photon emitted
3. A transformer rated at 10 kW is used to connect a 5 kV transmission line to a 240 V
4. The focal lengths of a converging lens are fᵥ and fᵣ for violet and red lights
5. A bullet loses 1/20 of its velocity after penetrating a plank.How many planks

Topics: Motion of system of Particles and Rigid Body (73)
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