Match List I with List II and select the correct answer from the codes given below the lists.  Codes:

In 's third law, the action and reaction forces
1.act on different bodies
2.act on the same body
3.are not always equal
4.are always equal
Choose the correct answer from the codes given below:

What should be done to increase the pitch of a string instrument?
I.Increase the length of the string used
II.Decrease the guage of the string used
III.Loosen the string
IV.Tighten the string

Which of the following have been found to be true regarding comets?
1.A comet cannot move in a circle.
2.The time that elapses between two returns of a comet to perihelion is called its period.
3.Enck's comet has the shortest known period-about 3.3 years.

Which of the following statements are true regarding heat?
1.Heat is a form of energy
2.Heat can be reflected by a mirror
3.Heat is an electromagnetic radiation
4.Heat cannot pass through vacuum

Copper wires are generally used for electrical power transmission instead of iron wires because

Match List I with List II and select the correct answer from the codes given below the lists.   Codes:

Consider the following statements about a thermos flask
1.It is a practical device in which the heat flowing into or out of the system by conduction, convection or radiation is reduced as much as possible.
2.It consists of a double-walled glass vessel.
3.The heat transfer by convection is minimised by silvering the surfaces and the radiation is minimised by evacuating the space between the walls.Of these, the correct ones are

Match List I (Parameters) with List II (Units of Length) and select the correct answer from the codes given below the lists.    Codes:

A person's spectacles have a power of-2.0. The spectacles have ____ and _____ are
1.converging lens
2.diverging lens
3.for short sight
4.for long sight