Refraction of Light — Physics STD 10 — Question

What type of lenses are used in spectacles worn by an old lady for knitting?

Two forces each of magnitude 2 N act vertically upward and downward respectively on two ends of a uniform rod of length 1 m, freely pivoted at its centre. Determine the resultant moment of forces about the mid-point of the rod.

In the following case write yes, if the work is being done and no if no work is being done.
A coolie standing with a heavy load on his head

Give two characteristic of the image formed by a concave lens.

Name the scientist who discovered Visible light

The specific latent heat of fusion of ice is 336 J g-1. Explain the meaning of its statement.

What are the SI units of specific resistance?

The power of a lens is negative. State whether it is convex or concave?

Give one example when:
Light energy changes to chemical energy.

Suggest one effective way for the safe disposal of nuclear waste.