Download Gravitation Worksheet

BUDS PUBLIC SCHOOL, DUBAI
PHYSICS WORKSHEET
TOPIC- Gravitation
Name:________________________
Class:11
Sec:___
Answer These Questions:1. What is meant by orbital velocity of a satellite? Obtain an expression for orbital velocity
of a satellite.
2. Define gravitational potential? Obtain expression for the gravitational potential energy
near the surface of the earth.
3. Express mass and density of earth in terms of ‘G’ and ‘g’. Show the variation of ‘g’ with
altitude and depth.
4. Discuss the variation in ‘g’ with altitude and depth.
5. Derive expression for escape velocity.
6. State and prove Kepler’s second and third law of planetary motion
7. How much faster than its present rate should earth rotate about its axis so that the weight
of a body at equator becomes zero?
8. A spaceship is stationed on mars. How much energy must be expended on the space ship
to launch it out of the solar system? Mass of the space ship =2000 kg; mass of the sun
=2x1030 kg; mass of the Mars =6.4 x10 23kg; radius of mars =3395km; radius of the orbit
of mars = 2.28 x108 km, G= 6.67 x 10-11Nm2Kg2.
9. Jupiter has mass 318 times that of earth and its radius is 11.2 times the earth’s radius.
Estimate the escape velocity of a body from Jupiter surface? Given that the escape
velocity from earth’s surface is 11.2 km/s.
10. Let us assume our galaxy consist of 2.5x1011stars each of one solar mass. How long will
a star of a distance of 50000 light years from a galactic centre take to complete one
revolution? Take the diameter of the Milky Way to be 105 light years.
11. How much below the surface does the acceleration due to gravity become 70% of its
value on the surface of the earth
12. If earth were a perfect sphere of radius 6.37x106m, rotating about its axis with a period of
one day (=8.64x104s). How much would be the acceleration due to gravity differ from
pole to equator?
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