Questions-1.Radiocarbon is produced in the atmosphere as a result of
A. collision between fast neutrons and nitrogen nuclei present in the atmosphere
B. action of ultraviolet light from the sun on atmospheric oxygen
C. action of solar radiations particularly cosmic rays on carbon dioxide present in the atmosphere
D. lightning discharge in atmosphere
2.It is easier to roll a stone up a sloping road than to lift it vertical upwards because
A. work done in rolling is more than in lifting
B. work done in lifting the stone is equal to rolling it
C. work done in both is same but the rate of doing work is less in rolling
D. work done in rolling a stone is less than in lifting it
3.The absorption of ink by blotting paper involves
A. viscosity of ink
B. capillary action phenomenon
C. diffusion of ink through the blotting
D. siphon action
4.Siphon will fail to work if
A. the densities of the liquid in the two vessels are equal
B. the level of the liquid in the two vessels are at the same height
C. both its limbs are of unequal length
D. the temperature of the liquids in the two vessels are the same
5.Large transformers, when used for some time, become very hot and are cooled by circulating oil. The heating of the transformer is due to
A. the heating effect of current alone
B. hysteresis loss alone
C. both the heating effect of current and hysteresis loss
D. intense sunlight at noon
6.Nuclear sizes are expressed in a unit named
A. Fermi B. angstrom
C. newton D. tesla
7.Stars appears to move from east to west because
A. all stars move from east to west
B. the earth rotates from west to east
C. the earth rotates from east to west
D. the background of the stars moves from west to east
8.Planets do not twinkle because
A. they emit light of a constant intensity
B. their distance from the earth does not change with time
C. they are very far away from the earth resulting in decrease in intensity of light
D. they are nearer to earth and hence we receive a greater amount of light and, therefore minor variations in the intensity are not noticeable
9.Metals are good conductors of electricity because
A. they contain free electrons
B. the atoms are lightly packed
C. they have high melting point
D. All of the above
10.Let a thin capillary tube be replaced with another tube of insufficient length then, we find water
A. will overflow
B. will not rise
C. depressed
D. change its meniscus
11.Out of the following pairs, choose the pair in which the physical quantities do not have identical dimension?
A. Pressure and Young's modules
B. Planck's constant and Angular momentum
C. Impulse and moment of force
D. Force and rate of change of linear momentum
12.If two bodies of different masses, initially at rest, are acted upon by the same force for the same time, then the both bodies acquire the same
A. velocity B. momentum
C. acceleration D. kinetic energy
13.Pick out the scalar quantity
A. force B. pressure
C. velocity D. acceleration
14.Rectifiers are used to convert
A. Direct current to Alternating current
B. Alternating current to Direct current
C. high voltage to low voltage
D. low voltage to high voltage
15.out of the following, which is not emitted by radioactive substance?
A. Electrons
B. Electromagnetic radiations
C. Alpha particles
D. Neutrons
16.Sound waves in air are
A. transverse B. longitudinal
C. electromagnetic D. polarised
17.Magnetism at the centre of a bar magnet is
A. minimum B. maximum
C. zero D. minimum or maximum
18.It is more difficult to walk on a sandy road than on a concrete road because
A. sand is soft and concreter is hard
B. the friction between sand and feet is less than that between concrete and feet
C. the friction between sand and feet is more than that between concrete and feet
D. the sand is grainy but concrete is smooth
19.Find the maximum velocity for the overturn of a car moving on a circular track of radius 100 m. The co-efficient of friction between the road and tyre is 0.2
A. 0.14 m/s
B. 140 m/s
C. 1.4 km/s
D. 14 m/s
20.Of the following properties of a wave, the one that is independent of the other is its
A. amplitude B. velocity
C. wavelength D. frequency
1.Option A
2.Option D
3.Option B
4.Option B
5.Option C
6.Option A
7.Option B
8.Option D
9.Option A
10.Option B
11.Option C
12.Option B
13.Option B
14.Option B
15.Option D
16.Option B
17.Option C
18.Option B
19.Option D
20.Option A