P0IITU07 - Gravitation qns

P0IITU07 - Gravitation qns - Q281. Astronauts in stable...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Page 1 of 1 Q281. Astronauts in stable orbits round the earth are in a state of weightlessness because (a) there is no gravitational force acting on them (b) the gravitational force of sun and earth balance (c) satellite has a acceleration equal to that of gravitational acceleration there (d) there is no atmosphere at the height at which the satellite more Q282. Which of the statements is false. The gravitational force between two bodies (a) depends on the magnitude of the masses of the bodies (b) the distribution of the mass in each body (c) becomes one fourth when the distance between them is doubled (d) depends on the nature of the medium between the bodies Q283. The gravitational field at P due to a uniform solid sphere of radius R and centre O is (a) inversely proportional to OP if OP R (b) inversely proportional to OP if OP < R (c) inversely proportional to square of OP if OP > P (d) directly proportional to square of OP if OP < R Q284. A string passes through a smooth hole O on a smooth horizontal table. A particle attached to one end of the string describes circular motion of radius r 0 on the with O as centre. The other end of the string is pulled vertically down slowly at constant speed when the distance of the particle from O is r ( < r 0 ) (a) its kinetic energy is unchanged (b) its kinetic energy has decreased (c) its kinetic energy has increased (d) its potential energy has increased Q285. The dimensions of G, the universal gravitation constant are (a) M 3 L 3 T - 2 (b) M - 1 L 2 T - 3 (c) M - 1 L 3 T - 2 (d) M - 1 L 3 T - 1 Q286. The escape velocity from a planet of mass M and radius R is given by (a) R / GM 2 (b) R / GM 2 1 (c) G / MR 2 (d) GM / R Q287. The value of acceleration due to gravity at a point above the surface of the earth is 9.8 m/s 2 . If the earth suddenly shrinks to half its size uniformly without any change in its mass, the value of g at that point will now be (a) 4.9 ms - 2 (b) 2 × 9.8 ms - 2 (c) 9.8 ms - 2 (d) 9.8/ 2 ms - 2 Q288. The value of acceleration due to gravity is minimum (a) at the equator (b) at the pole (c) at the centre of the earth (d) at the highest point on the surface of the earth Q289. The escape velocity from earth (a) velocity with which any body is thrown from the surface of the earth (b) velocity with which earth rotates abut its axis (c) velocity with which earth moves around the sun (d) the minimum velocity imparted to a body so that its escapes the gravitational attraction of the earth Q290. For a body launched from the surface of the earth with velocity equal to the escape velocity, on just escaping the gravitation pull of the earth (a) only its kinetic energy will be zero (b) only its potential energy will be zero (c) its total energy will be zero (d) both kinetic and potential energies will be zero Q291. The escape velocity for a rocket on earth is 11.2 km/sec. Its value on a planet where acceleration due to gravity is double that on the earth and whose diameter is double that of earth, will be (in km s
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/05/2011 for the course PHY 203 taught by Professor Grimaldi during the Spring '11 term at St. Mary NE.

Page1 / 6

P0IITU07 - Gravitation qns - Q281. Astronauts in stable...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online