To produce a parallel beam of light from a concave mirror, the distance at a which the lamp should be placed from the mirror is equal to

Similar Questions

Two radioactive elements A and B have half-lives of 100 and 50 years respectively. Samples of A and ...

An object is placed 36cm from a converging lens of focal length 24cm.If a real image which is 4cm hi...

The falling of light energy on a metal such that electrons are liberated from the metal is called ...

For photoelectric emission, the threshold frequency is the ...

During the nuclear reaction described by 235W →235X→231Y929391 the particles emitted are resp...

A member of the crew of a SPACESHIP experiences weightlessness in a space when they ...

What is the gravitational potential due to a point mass m at a distance from it? (G = gravitational ...

The distance between two successive crests of a water is 1m. lf a particle on the surface of the wat...

The speed of sound in air is 330ms-1. How far from the centre of a storm is an observer who hears a ...

The terminal voltage of a battery is 4.0V when supplying a current of 2.0A, and 2.0V when supplying ...