# Ch – 10 Gravitation

Q.1: The motion of the moon around the earth is due to the __________ force.

a) centrifugal

b) coriolis

c) centripetal

Q.2: The SI unit of pressure is ______.

a) pascal

b) newton

c) none

Q.3: Gravitation is a weak force unless ________ masses are involved.

a) large

b) small

c) equal

Q.4: In which of the following things, is the Archimedes’ principle applied ?

i) Lactometers

ii) Designing ships

iii) Hydrometers

a) only ii

b) only i

c) i, ii and iii

Q.5: According to the universal law of gravitation, the force between two objects is directly proportional to the product of their ____________.

a) heights

b) positions

c) masses

Q.6: The value of G was found by ________________.

a) Isaac Newton

b) Henry Cavendish

c) Johannes Kepler

Q.7: Which of the following is NOT a Kepler’s law ?

a) The cube of the mean distance of a planet from the Sun is proportional to the square of its orbital period T.

b) Every object in the universe attracts every other object with a force which is proportional to the product of their masses and inversely proportional to the square of the distance between them.

c) The line joining the planet and the Sun sweep equal areas in equal intervals of time.

Q.8: As the radius of the earth increases from the poles to the equator, the value of g becomes _________ at the poles than at the equator.

a) smaller

b) equal

c) greater

Q.9: The acceleration will be taken as __________, when it is in the direction of motion.

a) positive

b) negative

c) neutral

Q.10: The magnitude of the buoyant force depends on the ________ of the fluid.

a) colour

b) mass

c) density

1. c
2. a
3. a
4. c
5. c
6. b
7. b
8. c
9. a
10. c

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