What is the region of a shadow that receives some light from the source and gets partially illuminate called?

How much light does the umbra region of a shadow receive from the source?

How does the nature of a shadow depend on the light source?

What is the cell that receives a recombinant gene called ?

What is the shape of the wavefront diverging from a point source of light?

For light diverging from a point source

To get an echo, the reflecting wall should be about 17 m from the source

The darkest part of a shadow where no light falls at all is called the penumbra region.

A: When a tiny circular obstacle is placed in the path of light from a distant source, a bright spot is seen at the centre of the shadow of the obstacle. R: Waves diffracted from the edge of the circular obstacle interfere constructively at the centre of the shadow producing a bright spot.

The wavelength of light received from a galaxy is 10% greater than that received from identical source on the earth. The velocity of the galaxy relative to the earth is

An astronomical telescope in normal adjustment receives light from a distant source S . The tube length is now decreased slightly