RamanFlame Institute - Part 6

Home
Author: Raman
Page 6

Escape velocity on a planet is ve . If radius of the planet remains same and mass becomes 4 times, the escape velocity becomes

(a) 4 ve (b) 2 ve (c) ve …

Read More

The escape velocity of an object from the earth depends upon the mass of the earth (M), its mean density (p), its radius (R) and the gravitational constant (G). Thus the formula for escape velocity is

Answer: a (5)

Read More

A missile is launched with a velocity less than the escape velocity. The sum of its kinetic and potential energy is

(a) Positive (b) Negative (c) Zero (d) May be positive or negative depending upon its initial velocity Answer: b (8)

Read More

If g is the acceleration due to gravity at the earth’s surface and r is the radius of the earth, the escape velocity for the body to escape out of earth’s gravitational field is

(a) gr (b) √2gr (c) g/r (d) r/g Answer: b (4)

Read More

The escape velocity for a rocket from earth is 11.2 km/sec. Its value on a planet where acceleration due to gravity is double that on the earth and diameter of the planet is twice that of earth will be in km/sec

(a) 11.2 (b) 5.6 (c) 22.4 (d) 53.6 Answer: c (6)

Read More

The escape velocity from the earth is about 11 km/second. The escape velocity from a planet having twice the radius and the same mean density as the earth, is

(a) 22 km/sec (b) 11 km/s (c) 5.5 km/sec (d) 15.5 km/sec Answer: a (6)

Read More

For the moon to cease to remain the earth’s satellite, its orbital velocity has to increase by a factor of

(a) 2 (b) √ 2 (c) 1/√2 (d) √3 Answer: b (7)

Read More

The escape velocity of a particle of mass m varies as

(a) m2 (b) m (c) m0 (d) m-1 Answer: c (7)

Read More

The escape velocity of a projectile from the earth is approximately

(a) 11.2 m/sec (b) 112 km/sec (c) 11.2 km/sec (d) 11200 km/sec Answer: c (9)

Read More

The escape velocity of a sphere of mass m from earth having mass M and radius R is given by

Answer: a (14)

Read More

Gas escapes from the surface of a planet because it acquires an escape velocity. The escape velocity will depend on which of the following factors : I. Mass of the planet II. Mass of the particle escaping III. Temperature of the planet IV. Radius of the planet Select the correct answer from the codes given below :

(a) I and II (b) II and IV (c) I and IV (d) I, III and IV Answer: c (4)

Read More

A particle falls towards earth from infinity. It’s velocity on reaching the earth would be

(a) Infinity (b) √2 gR (c) 2√gR (d) Zero Answer: b (7)

Read More

A body of mass m kg. starts falling from a point 2R above the Earth’s surface. Its kinetic energy when it has fallen to a point ‘R’ above the Earth’s surface [R-Radius of Earth, M-Mass of Earth, G-Gravitational Constant]

(a) 1/4 (GMm /R) (b) 1/6 ( (GMm /R) (c) 2/3 (GMm /R) (d) 1/3 (GMm /R) Answer: b (41)

Read More

A body is projected vertically upwards from the surface of a planet of radius R with a velocity equal to half the escape velocity for that planet. The maximum height attained by the body is

(a) R/3 (b) R/2 (c) R/4 (d) R/5 Answer: a (4)

Read More

In some region, the gravitational field is zero. The gravitational potential in this region

(a) Must be variable (b) Must be constant (c) Cannot be zero (d) Must be zero Answer: b (10)

Read More

Radius of orbit of satellite of earth is R. Its kinetic energy is proportional to

(a) 1/R (b) 1 /√R (c) R …

Read More

The kinetic energy needed to project a body of mass m from the earth surface (radius R) to infinity is

(a) mgR/2 (b) 2 mgR (c) mgR (d) mgR/4 Answer: c (4)

Read More

Energy required to move a body of mass m from an orbit of radius 2R to 3R is

(a) GMm/ 12R2 (b) GMm/ 3R2 (c) GMm / 8R (d) GMm / 6R Answer: d (6)

Read More

A body of mass m is placed on the earth’s surface. It is taken from the earth’s surface to a height h=3R . The change in gravitational potential energy of the body is

(a) 2/3 mgR (b) 3/4 mgR (c) mgR/2 (d) mgR/4 Answer: b (5)

Read More

Escape velocity of a body of 1 kg mass on a planet is 100 m/sec. Gravitational Potential energy of the body at the Planet is

(a) – 5000 J (b) – 1000 J (c) – 2400 J (d) 5000 J Answer: A (5)

Read More

The gravitational potential energy of a body of mass ‘m’ at the earth’s surface -mgRe . Its gravitational potential energy at a height Re from the earth’s surface will be (Here is Re the radius of the earth)

(a) -2 mgR e (b) 2 mgR e (c) 1/2 mgR e (d) -(1/2) mgR e Answer: d (4)

Read More

What is the intensity of gravitational field of the centre of a spherical shell

(a) Gm/R2 (b) g (c) Zero (d) None of these Answer: c (10)

Read More

There are two bodies of masses 100 kg and 10000 kg separated by a distance 1 m. At what distance from the smaller body, the intensity of gravitational field will be zero

(a) 1/9 m (b) 1/10 m (c) 1/11 m (d) 10/11 m Answer: c (5)

Read More

A rocket is launched with velocity 10 km/s. If radius of earth is R, then maximum height attained by it will be

(a) 2R (b) 3R (c) 4R (d) 5R Answer: c (11)

Read More

If mass of earth is M, radius is R and gravitational constant is G, then work done to take 1 kg mass from earth surface to infinity will be

(a) √GM/2R (b) GM/R (c) 2√GM/R (d) GM/2R Answer: b (4)

Read More

The masses and radii of the earth and moon are M1,R1 and M2,R2 respectively. Their centres are distance d apart. The minimum velocity with which a particle of mass m should be projected from a point midway between their centres so that it escapes to infinity is

answer-a (7)

Read More

The change in potential energy, when a body of mass m is raised to a height nR from the earth’s surface is (R = Radius of earth)

(a) mgR n/n-1 (b) nmgR (c) mgR n2/n2+1 (d) mgR n/n+1 Answer: …

Read More

The mass of the earth is 6.00 × 10^24 kg and that of the moon is 7.40 × 10^22 kg . The constant of gravitation G=6.67 × 10^-11 N-M^2/kg^2. The potential energy of the system is -7.79 × 10^28 joules . The mean distance between the earth and moon is

(a) 3.80×108 metres (b) 3.37 ×106 metres (c) 7.60×104 metres (d) 1.90×102 metres Answer: a (43)

Read More

A satellite revolves around the earth in an elliptical orbit. Its speed

(a) Is the same at all points in the orbit (b) Is greatest when it is closest to the earth (c) Is greatest when it is farthest from the earth (d) Goes on increasing or decreasing continuously depending upon the …

Read More

A small satellite is revolving near earth’s surface. Its orbital velocity will be nearly

(a) 8 km/sec (b) 11.2 km/sec (c) 4 km/sec (d) 6 km/sec Answer: a (11)

Read More

A geostationary satellite

(a) Revolves about the polar axis (b) Has a time period less than that of the near earth satellite (c) Moves faster than a near earth satellite (d) Is stationary in the space Answer: a (12)

Read More

Two satellites A and B go round a planet P in circular orbits having radii 4R and R If the speed of the satellite A is 3V, the speed of the satellite B will be.

(a) 12 V (b) 6 V (c) 4/3 V (d) 3/2V Answer: b (7)

Read More

The relay satellite transmits the T.V. programme continuously from one part of the world to another because its

(a) Period is greater than the period of rotation of the earth (b) Period is less than the period of rotation of the earth about its axis (c) Period has no relation with the period of the earth about its …

Read More

11. If a satellite is orbiting the earth very close to its surface, then the orbital velocity mainly depends on

(a) The mass of the satellite only (b) The radius of the earth only (c) The orbital radius only (d) The mass of the earth only Answer: b (8)

Read More

The period of a satellite in a circular orbit around a planet is independent of

(a) The mass of the planet (b) The radius of the planet (c) The mass of the satellite (d) All the three parameters (a), (b) and (c) Answer: c (9)

Read More

The mean radius of the earth is R, its angular speed on its own axis is ω and the acceleration due to gravity at earth’s surface is g. The cube of the radius of the orbit of a geostationary satellite will be

(a) R2g/ ω (b) R2 ω2/g (c) Rg/ ω2 …

Read More

25. Orbital velocity of earth’s satellite near the surface is 7 km/s. When the radius of the orbit is 4 times than that of earth’s radius, then orbital velocity in that orbit is

(a) 3.5 km/s (b) 7 km/s (c) 72 km/s (d) 14 km/s Answer: a (14)

Read More

The time period of a geostationary satellite is

(a) 24 hours (b) 12 hours (c) 365 days (d) One month Answer: a (13)

Read More

Orbital velocity of an artificial satellite does not depend upon

(a) Mass of the earth (b) Mass of the satellite (c) Radius of the earth (d) Acceleration due to gravity Answer: b (12)

Read More

A satellite is moving around the earth with speed v in a circular orbit of radius r. If the orbit radius is decreased by 1%, its speed will

(a) Increase by 1% (b) Increase by 0.5% (c) Decrease by 1% (d) Decrease by 0.5% Answer: b (4)

Read More

<
1
…
5
6
7
>

error: Content is protected !!

Call Now Button