A comet is different from a planet because _________ .
AIt has light of its own
BIts orbit is more elliptical
CIt does not orbit around a host star
DIt is oval in shape
Ali was asked about importance of non-living things. He made four statements. Select the correct one.
A They are needed by some living things to feed upon.
B Living things need a man-made, non-living thing to breathe.
C Non-living things are always required by living things to move from one place to another.
D Both (A) and (B)
The given diagram shows a respirometer that is used to measure gaseous exchange in pea seeds. The apparatus is maintained at a constant temperature.
Which of the following is incorrect regarding this?
AThe gas pressure in X will fall as O2 is absorbed during respiration and CO2 is absorbed by potassium hydroxide solution.
BThe fluid level at Y will fall to compensate the loss of pressure in X.
CThe gas pressure at X will rise as O2 is given out by seeds and CO2 is released by potassium hydroxide solution.
DThe fluid level at Z will rise due to loss of pressure at X.
Which of the following events will result in a decrease in the population of butterflies?
1. Increase in the population of birds
2. Increase in the supply of plant fertilisers
3. Reduction in the number of green plants
4. Increased use of insecticides by man on gardens and green belts
A1, 2 and 3
B1, 2 and 4
C1, 3 and 4
D2, 3 and 4
A scooterist moving with a speed of 36 km h-1 sees a child standing in the middle of the road. He applies the brakes and brings the scooter to rest in 5 s just in time to save child. If mass of the scooter and driver is 300 kg, the average retarding force on the scooter is
A6 × 107 g cm s-2
B6 × 104 g m s-2
C6 × 105 kg cm s-2
D6 × 103 kg m s-2
Match the columns and select the correct option.
|(A) Short, hard and pointed||(1) Duck|
|(B) Long and pointed||(2) Humming bird|
|(C) Strong and hooked beak||(3) Pigeon|
|Broad and flat||(4) Sparrow|
Aa-3; b-1, 6; c-4; d-2, 5
Ba-4; b-3, 6; c-1; d-2, 5
Ca-3, 4; b-2,6; c-5; d-1
Da-2, 6; b-1; c-5; d-3, 4
No correct answer is "OPTION D"
Which of the following options is correct for the object having a straight line motion represented by the graph shown in figure?
(a) The object moves with constantly increasing velocity from O to A and then it moves with constant velocity.
(b) Velocity of the object increases uniformly.
(c) Average velocity is zero.
(d) The graph shown is impossible.