1. Which of the following is true about the universe?
a) It is an open system
b) It is a closed system
c) It is an isolated system
d) It is an international system
Explanation: In spite of all the violent phenomenon occurring in this universe all the time, the total energy if the universe remains constant. The total energy remains constant only in an isolated system. Thus the universe is an example of an isolated system.
2. Which of the following holds good in all natural processes?
a) The Doppler Effect
b) Newton’s law of gravitation
c) Electromagnetic law
d) Lenz’s law
Explanation: It states that every body in the universe is attracted to every other body with a force directly proportional to the product of their masses and inversely proportional to the square of the distance between them. Hence it holds good in all natural processes.
3. Strong nuclear force is independent of charge.
a) True
b) False
Explanation: Nuclear forces between a proton and proton, a neutron and neutron are nearly equally strong. This indicated that the strong nuclear force does not depend on the charge on the charge of the nucleons.
4. Which of the following leads to the law of conservation of energy?
a) Gravity
b) Isotropy
c) Nuclear force
d) Homogeneity of time
Explanation: If we perform an experiment at a certain place today and repeat it after one yer at the same place, we obtain the same results. This symmetry of nature with respect to translation or displacement of time is called homogeneity of time and it leads to the law of conservation of energy.
5. Which of the following leads to the law of conservation of angular momentum?
a) Isotropy of space
b) Homogeneity of time
c) Nuclear force
d) Gravity
Explanation: Law of nature takes the same form everywhere in the universe. That is there is no particular location in the universe. This symmetry of the laws of nature with respect to translation in space id called homogeneity of space and gives rise to the law of conservation of linear momentum.
6. Which of the following is the SI unit of luminous intensity?
a) Sterdian
b) Radian
c) Mole
d) Candela
Explanation: Candela is the SI unit of luminous intensity. One candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540×1012 hertz and that has a radiant intensity of 1/683 watt per sterdian in that direction.
7. Sterdian is the SI unit of which of the following?
a) Phase angle
b) Luminous intensity
c) Mass
d) Solid angle
Explanation: Sterdian is defined as the solid angle subtended at the centre of a sphere by a surface of the sphere equal in area to that of a square, having each side equal to the radius of the sphere.
8. How many light years are there in one metre?
a) 9.46×1015ly
b) 1.057×10-16ly
c) 1ly
d) 1×10-16ly
Explanation: 1 light year = 9.46×1015m
1m = 1/(9.46×1015)ly = 1.057×10-16ly.
9. The radius of gold nucleus is 41.3fermi. Express its volume in m3.
a) 41.3×10-15 m3
b) 2.95×10-40 m3
c) 4.19 m3
d) 29.33 m3
Explanation: Radius = 41.3 Fermi = 41.3×10-15m
V = 4/3 πr3 = 2.95×10-40 m3.
10. Convert an acceleration of 2km/h2 into cm/s2.
a) 2×105 cm/s2
b) 0.0027 cm/s2
c) 0.0154 cm/s2
d) 0.055 cm/s2
Explanation: a = 2 km/h2
a = 0.0154 cm/s2.