A small body is kept at a distance of 7 cm from the centre of a gramophone disc. The disc starts rotating with gradually increasing speed and the body is just on the verge of being thrown off when the disc rotates at 60 times a minute. What will be the speed of the disc when the body, kept at a distance of 12 cm from the centre, is just thrown off? What will be the rotational speed, when a body of double the mass is kept at the previous position of 7 cm away from the centre?

A small body is kept at a distance of 7 cm from the centre of a gramop

1.	A small body is kept at a distance of 7 cm from the centre of a gramophone disc. The disc starts rotating with gradually increasing speed and the body is just on the verge of being thrown off when the disc rotates at 60 times a minute. What will be the speed of the disc when the body, kept at a distance of 12 cm from the centre, is just thrown off? What will be the rotational speed, when a body of double the mass is kept at the previous position of 7 cm away from the centre?
Answer» ANSWER :46 RPM, 60 rpm