Physics Past Questions and Answers

What happens to a water pool on a day when the humidity of the air is very low?

A satellite moves in a circular orbit of radius 4R round the earth. The acceleration of the satellite in terms of g is

I.Chemical II.Sound III.Electricity
Which of the above forms of energy can directly be converted to light energy?

If the distance between the object and the pinhole of a pinhole camera is reduced by half the size of the image of the object

An object is placed 15cm in front of a plane mirror. If the mirror is moved further 5cm away from the object and the image is