271: AIDS is:
(1) Caused by virus
(2) Carried by body fluid, blood and serum
(3) Found mostly in males
(4) Found mostly in homosexuals
(a) 1 and 4 are correct
(b) 1,2 and 4 are correct
(c) 2 and 3 are correct
(d) 1, 2, 3 and 4 are correct
272: A parachutist jumps from a height of 5000 meters. The relationship between his falling speed, 'v' and the distance fallen through 'd' is best represented as
Explanation:
When parachutist jumps, he gains speed with distance and resistance from air starts acting proportional to velocity. After sometime the force of resistance of air will be equal to the weigh of the body (mg) leading to a state where body attains fixed velocity.
273: Man cannot digest cellulose whereas cows can do so because
(a) Their gut contains certain bacteria capable of digesting cellulose
(b) They have a many-chambered stomach
(c) They have efficient grinding molars
(d) They produce an enzyme cellulose which can digest cellulose
274: The variations in temperatures from 0 degree C to 100 degree C with respect to time of two liquids P, Q are shown in the graph given below :
Which one of the following statement is correct ?
(a) During heating, liquid P remained hotter than liquid Q throughout
(b) At no point of time during heating did the two liquids have the same temperature
(c) P attained the temperature of 100 degree C faster than Q
(d) Q attained the temperature of 100 degree C faster than P
Explanation:
Q attained the temperature of 100 degree C faster than P.
275: Pulse reading is done by doctors to find out:
(a) Temperature
(b) Heart beat
(c) Blood pressure
(d) Respiration rate