A man claps near a cliff and echo is heard after 5 s. If the velocity of sound is `346 ms^-1`, then what will be the distance between the man and the cliff ?

A ship produces ultrasonic sound which is collected in 3.42 s after reflection from the surface of sea. If the velocity of ultrasonics is 1531ms^-1 , then what is the distance of sea surface from sea ?

Two electrons are moving towards each other, each with a velocity of 10^6ms^-1 . What will be closest distance of approach between them?

A point source of gamma - radiatonhas a half-life of 30 minutes.The intitial count rate recorded by Geiger counter placed 2 m from the source is 360 s^(-1) .The distnace between the counter and the source is altered.After 1.5 hours,the count rate recorded is 5 s^(-1) .What is th new distnace between the counter and the source?

Two points are located at a distance of 10 m and 15 m from the source of oscillation .theperiod of oscillation is 0.05 sec and the velocity of the wave is 300 m s^(-1) .What is the phase difference between the oscillation of two points?

A man throws a ball of mass 0.5 kg vertically upwards with a velocity of 1ms^( -1) . What will be its initial momentum ? What would be its momentum at the highest point of its reach ?

A stone of 1 kg is thrown with a velocity of 20 ms^( -1) across the frozen surface of a lake and comes to rest after travelling a distance of 50 m. What is the force of friction between the stone and the ice ?