Question : A metal ball and a rubber ball, both having the same mass, strike a wall normally with the same velocity. The rubber ball rebounds and the metal ball does not rebound. It can be concluded that:

Option 1: The rubber ball suffers a greater change in momentum

Option 2: The metal ball suffers a greater change in momentum

Option 3: Both suffer the same change in momentum

Option 4: The initial momentum of the rubber ball is greater than that of the metal ball

Question : Metal tea pots have wooden handles because:

Option 1: wood is bad conductor of heat

Option 2: it prevents electric shock

Option 3: it gives beauty to the pots

Option 4: it is hygenic

Question : Air is said to be saturated when -

Option 1: It contains the maximum content of water vapour.

Option 2: Its pressure is minimum.

Option 3: Its thickness is maximum.

Option 4: It blows over the barren land.

Question : A cuboidal water tank is 12 m long, 9 m wide and 7.5 m deep. How many litres of water can it hold?

Option 1: 840000

Option 2: 805000

Option 3: 780000

Option 4: 810000

Question : Refrigerators keep food unspoiled because

Option 1: at its low temperature bacteria and moulds are inactive

Option 2: at its low temperature, the germs are killed

Option 3: at its low temperature, the germs are frozen

Option 4: it sterilizes the food