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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

A 6 × 107 g cm s^-2
B 6 × 104 g m s^-2
C 6 × 105 kg cm s^-2
D 6 × 103 kg m s^-2

Select the odd one out.

A
B
C
D

Study the given figure carefully and answer the following question.

After turning 180° clockwise and then 135° anti-clockwise, Shivam is facing the Theatre. Where was he facing before the turns?

AFood centre
BTemple
CMarket
DHospital

You are standing upright in a room in front of a vertical mirror. In this mirror, you can see from your position, only the upper two-third part of your body. You wish to see the full image of your body in the mirror. Which combination of the following three courses of action will achieve this?
I. Move away from the mirror
II. Move towards the mirror
III. Use a mirror whose height will allow you to see your full image

A I only
B II only
C III only
D Either I or III

Which of the following statements are correct?
I. Temperature changes during the change of a state.
II. Dry ice gets converted directly into gaseous state under normal atmospheric conditions.
III. Higher boiling point of liquid indicates weaker intermolecular forces.
IV. Latent heat of vaporisation is generally higher than the latent heat of fusion for a substance.

A I and IV only
B II and IV only
C II and III only
D III and IV only

Genetic drift can be defined as

A A random change in gene frequencies of the remaining population, occurring by chance fluctuations
B A change in an allele due to alteration in the DNA molecule
C A change in gene frequencies due to exchange of genes between different populations
D A product of natural selection.

Study the given experimental set-up.

By measuring the movement of the oil drop in the apparatus, what can be investigated?

A Carbon dioxide is released during germination
B Heat is released during germination
C Oxygen is used during germination
D Water is produced during germination

__________ give(s) us energy to work and play.

A Bread
B Sugar
C Potato
D All of these