Force, Work, Power and Energy — Physics STD 10 — Question

What is a superconductor? Give one example of it.

Arrange the speeds of sound in gases, solids, and liquids in ascending order.

What is dynomo (a.c. generator)? State the principle on which it works.

In what way does an ‘Ideal machine’ differ from a ‘Practical machine’?

Is energy a scalar or a vector physical quantity?

With reference to magnitude of force and its direction, how does centripetal force differ from centrifugal force?

Light of a single colour is passed through a liquid having a piece of glass suspended in it. On changing the temperature of liquid, at a particular temperature the glass piece is not seen.
When is the glass piece not seen?

Name the device used to transform 12 V a.c. to 200V a.c. Name the principal on which it
works.

Name the forms of energy which a wound-up watch spring possesses.

In the following case write yes, if the work is being done and no if no work is being done.
A man moving on the rough ground.