501: The working principle of a washing machine is

(a) centrifugation

(b) dialysis

(c) reverse osmosis

(d) diffusion
Explanation:
From the given diagram, the height will be more if the intial inclination is more.
502: On the Moon, astronauts inflate a rubber balloon with hydrogen gas and release it at a height of 2 metres. The balloon will:

(a) Fall down

(b) Go upwards

(c) Remain at the height of 2 metres

(d) First go up and finally come down
503: Which one of the following is not a digestive enzyme in the human systems?

(a) Trypsin
(b) Gastrin
(c) Yellow and violet
(d) Indigo and yellow

504: The characteristic odour of garlic is due to

(a) a chloro compound
(b) a sulphur compound
(c) a fluorine compound
(d) acetic acid
Explanation:
Characteristic odour of Onion and Garlic is due to sulphur compounds Allyl propyl disulphide and Diallyl disulphide respectively.
505: The medicines which are used to treat diseases caused by allergy are known as

(a) Analgesics

(b) Antihistamines

(c) Antipyretics

(d) Allergens