With what velocity a person should move so that he hears an octave of the note produced by a source at rest?

The radius of our galaxy is about 3 xx 10 ^(20)m .With what speed should a person travel so that he can reach from the centre of the galaxy to its edge in 20 years of his lifetime ?

A person can hear frequencies only upto 10kHz. A steel piano pipe wire 50cm long of mass 5g is streched with a tension of 400N. The number of the hightest overtone of the sound produced by this plano wire that the person can hear is

At what speed should a source of sound move so that observer finds the apparent frequency equal to half of the original frequency ?

With what velocity should a particle be projected so that its height becomes equal to radius of earth?

An object of mass m is moving with a constant velocity upsilon How much work should be done on the object in order to bring the object to rest ?

Two sources S_1 and S_2 of sound having frequencies 338 Hz and 342 Hz are separated by a large distance. The speed of sound is 340 ms^(-1). With what velocity should an observer move from source S_2 to S_1 so that he hears no beats?

A and B are two identical sound sources cachemitting a note of frequency 1000 Hz. A person moves from A to B along the line joining the two sources. How fast should be move to that he has 7 beats per second. velocity of sound 330 m/s ?

A source of sound emitting a note of frequency 200 Hz moves towards an observer with a velocity v equal to the velocity of sound. If the observer also moves away from the source with the same velocity v, the apparent frequency heard by the observer is

A person climbs up a stalled escalator in 60s. If standing on the same but escalator running with constant velocity, he takes 40 s. How much time is taken by the person to walk up the moving escalator?

A truck is moving with a constant velocity of 54 km h^-1 . In which direction (angle with the direction of motion of truck) should a stone be projected up with a velocity of 20 ms^-1 , from the floor of the truck of the truck, so as to appear at right angles to the truck, for a person standing on earth ?