Physics · 2018
JEE Main · 15 April 2018, Shift 2 · Q5
A disc rotates about its axis of symmetry in a horizontal plane at a steady rate of 3.5 revolutions per second. A coin placed at a distance of 1.25…
A disc rotates about its axis of symmetry in a horizontal plane at a steady rate of $\displaystyle 3.5$ revolutions per second. A coin placed at a distance of $\displaystyle 1.25$ cm from the axis of rotation remains at rest on the disc. The coefficient of friction between the coin and the disc is : $\displaystyle \left(\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^2\right)$
Official answer
(4)
$\displaystyle 0.6$
More from Circular Motion
- A tube of length 50 cm is filled completely with an incompressible liquid of mass 250 g and closed at both ends. The tube is then rotated in…2022
- A stone tied to 180 cm long string at its end is making 28 revolutions in horizontal circle in every minute. The magnitude of acceleration of stone…2023
- A pendulum of length 2 m consists of a wooden bob of mass 50 g. A bullet of mass 75 g is fired towards the stationary bob with a speed v. The bullet…2022
- A small bob tied at one end of a thin string of length 1 m is describing a vertical circle so that the maximum and minimum tension in the string are…2021
- A particle of mass m is fixed to one end of a light spring having force constant k and unstretched length l. The other end is fixed. The system is…2020
- The given figure shows a loop-the-loop track having radius 760 c m. A car without engine starts from a platform at a distance ' h ' above the top of…2021
- A particle is moving with a uniform speed in a circular orbit of radius R in a central force inversely proportional to the n^th power of R. If the…2018
- A car is moving with a constant speed of 20 m / s in a circular horizontal track of radius 40 m. A bob is suspended from the roof of the car by a…2023
JEE Main 2018 Physics question, with the answer from NTA’s final answer key. Where our answers come from.