When a knife is sharpened with the help of a rotation grinding stone, the spark always travel tangential to it.Why ?

When a kinife is sharpened with the help of a rotation grinding stone, the speerk always travel tangentiall to it .Why ?

When the cutting edge of a knife is put against a fast rotating stone to sharpen it, sparks are seen to fly. Explain the reason.

A stone tied at the end of string is whirled in a circle. If the string break, the stone flies away tangentially . Why ?

When a stone is thrown up, it reach it reaches a certain height and then stars falling down. Why ?

Assertion When a car takes a circular turn on a horizontal road, then normal reaction on inner wheels is always less than the normal reaction on outer wheels. Reason This is for rotational equilibrium of car.

A disc of mass M kg and radius R metre is rotating at an angular speed of omega rad/s when the motor is switched off. Neglecting the friction at the axie, the force that must be applied tangentially to the wheel to bring it to rest time t is

A stone is projected horizontally with speed u from the top of a tower of height h. (a) Calculate the radius of curvature of the path of the stone at the point where its tangential and radial accelerations are equal. (b) What shall be the height (h) of the tower so that radius of curvature of the path is always less than the value obtained in (a) above.

Why does a ray of light bend when it travels from one medium to another.