When we project a mobile screen in front of a wall , we only see the white light but r unable to see the written matter on it why ? if this question seems to be undigesting , try this for once n think.

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 10.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.90 m/s; (b) he is then lifted at the constant speed of 4.90 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 68.0 kg rescue by the force lifting him during each stage?

When an object is heated it contracts. a. true b. false

Aball has an initial velocity of 3 m/s. if there is no friction, what is the highest it could roll?