Physics

The radii of circular orbits of two satellites A and B of the earth, are 4R and R, respectively. If speed of satellite A is 2V, then the speed of satellite B will be

The angular frequency of a simple pendulum is Ω rad/s. Now the length is made one fourth of the original length, the angular frequency becomes

A body of mass M is rotating in a vertical circle of radius r with critical speed. The difference in its kinetic energy at the top and the bottom is

Two trains 101 m and 99 m in length are running in opposite direction with velocities 54 km/h and 36 km/h. In what time they will completely cross each other?

To measure light intensity we use

After one alpha particle emission and one b^– particle emission from a nucleus

The Boolean equation for the circuit as shown in figure is

 

When light of maximum wavelength 300 nm falls on a photoelectric emitter, photoelectrons are liberated. For another emitter however light of maximum wavelength 600 nm causes photoelectric emission. The ratio of work functions of first emitter to second emitter will be

Rainbow is formed due to

A defective eye cannot see close objects clearly because their image is formed