Write a paragraph about the importance of physical exercise.
Describe the most impressive person you have ever met.
The energy that can be extracted from a storage battery is always less than the energy that goes into it while charging. Why?
Water boiled in an electric kettle for 15 minutes after being switched on. Using the same main supply, should the length of the heating element be increased or decreased if the water is to boil in 10 minutes. Explain.
Write an essay on national unity for development with reference to Nepal.
What are the conditions for sustained interference of light?
A beam of light is reflected by a rotating mirror onto a fixed mirror, which sends it back to the rotating mirror which it is again reflected making an angle of 18° with its original direction. The distance between the two mirrors is 10 km and the rotating mirror is making 375 revolutions per second. calculate the velocity of light.
Describe Michelson's method for determining the speed of light.
When monochromatic light incidents on a surface, the reflected and refracted wave will have the same frequency. Why?
An observer traveling with a constant velocity of 20 m/s, passes close to a stationary source of sound and notices that there is a change of frequency of 50 hz as he passes the source. What is the frequency of the source? Speed of the sound in air = 340 m/s