A man M1 of mass 80 kg runs up a staircase in 15s. Another man M2 also of mass 80 kg runs up the same staircase in 20s. The ratio of the power developed by them will be
The half-life of a certain element is 3.5 days at STP. If the temperature is doubled and
pressure is reduced to half then half-life of the same element will be:
A whistle is revolved with high speed in a horizontal circle of radius R. to an observer at the centre of the circle the frequency of the whistle will appear to be:
If the radius of the circular path of particle going around the circle is doubled without changing its frequency of
rotation, then centripetal force on it is.
A rigid uniform bar of length 2.4 m is pivoted horizontally at its mid-point, weights are hung from two points
of the bar as shown in diagram. To maintain horizontal equilibrium, a couple is applied to the bar:
What is the torque and the direction of couple?
Light of frequency 2 times the threshold frequency is incident on the metalsurface. Ifthe frequency is by quartered and intensity is doubled, the photoelectric becomes
