If a man walks along the four sides of a square ground with speeds `v_1`, `v_2`,`v_3` and `v_4` km/hour respectively, then what would be his average speed?

Five molecules of a gas are moving with speed 1, 2, 3, 4, 5 km/sec. What is their root mean square speed ?

A water fountain on the ground sprinkles water all around it. If the speed of water coming out of the fountain is v , then what will be the total area around the fountain that gets wet ?

Two bodies having masses m_(1) and m_(2) are dropped from heights h_(1) and h_(2) respectively. They reach the ground after times t_(1) and t_(2) and strike the ground with velocities v_(1) and v_(2) respectively. Choose the correct relations from the following:

A man travels from Kalighat to Tarakeswar with a uniform speed of u km/h and returns from Tarakeswar to Kalighat with uniform speed of v km/h. Show that his average speed is the harmonic mean between u and v.

When a string is divided into three segments of length l_(1) , l_(2), and l_(3) the fundamental frequencies of these three segments are v_(1) , v_(2) and v_(3) respectively . The original fundamental frequency (v) of the string is

The radius of a planet is double than that of the earth but their average densities are the same. If the escape velocities of the planet and the earth are v_p and v_e respectively, then prove that v_p=2v_e .

A man travels a certain distance with a uniform speed of 5 km/h ad returns the same distance with a uniform speed of 4km/h. What is the average speed of the man?