NEET Physics Motion of Satellites Escape Speed and Orbital Velocity MCQs Set A

a)

b)

c) Zero

d)

Answer:

Question:  To have an earth synchronous satellite it should be launched at the proper height moving from

a) west to east in an equatorial plane

b) south to north in a polar plane

c) east to west in an equatorial plane

d) north to south in a polar plane

Answer: west to east in an equatorial plane

Question: A missile is launched with a velocity less than escape velocity. The sum of its kinetic and potential energies is

a) negative

b) positive

c) zero

d) may be positive, negative or zero.

Answer: negative

Question: The orbital speed of Jupiter is

a) less than the orbital speed of earth

b) greater than the orbital speed of earth

c) equal to the orbital speed of earth

d) zero

Answer:  less than the orbital speed of earth

Question:  The total energy of a circularly orbiting satellite is

a) half the potential energy of the satellite

b) twice the potential energy of the satellite

c) half the kinetic energy of the satellite

d) twice the kinetic energy of the satellite

Answer: half the potential energy of the satellite

Question: Geo-stationary satellite is one which

a) revolves round the earth at a suitable height with same angular velocity and in the same direction as earth does about its own axis

b) None of these

c) revolves like other satellites but in the opposite direction of earth’s rotation

d) remains stationary at a fixed height from the earth’s surface

Answer: revolves round the earth at a suitable height with same angular velocity and in the same direction as earth does about its own axis

Question: An artificial satellite orbiting the earth does not fall down because the earth’s attraction

a) produces the necessary acceleration of its motion in a curved path

b) is balanced by the viscous drag produced by the atmosphere

c) vanishes at such distances

d) is balanced by the attraction of the moon

Answer:  produces the necessary acceleration of its motion in a curved path

Question:  The minimum and maximum distances of a satellite from centre of earth are 2R and 4R respectively, where R is the radius of earth. The minimum and maximum speeds of the satellite will be

a)

b)

c) Both

d) None of these

Answer:

Question: The radius of the earth is reduced by 4%. The mass of the earth remains unchanged. What will be the change in escape velocity?

a) Increased by 2%

b) Increased by 6%

c) Decreased by 4%

d) Decreased by 8%

Answer: Increased by 2%

Question:  Time period of a simple pendulum inside a satellite orbiting earth is

a)

b) T

c) 2 T

d) zero

Answer: 

Question: A person sitting in a chair in a satellite feels weightless because

a) the normal force is zero

b) the person in satellite is not accelerated.

c) the normal force bythe chair on the person balances the earth's attraction

d) the earth does not attract the objects in a satellite

Answer: the normal force is zero

Question: The relay satellite transmits the TV programme continuously from one part of the world to another because its

a) period is equal to the period of rotation of the earth about its axis

b) period has no relation with the period of the earth about its axis

c) period is less than the period of rotation of the earth about its axis

d) period is greater than the period of rotation of the earth

Answer: period is equal to the period of rotation of the earth about its axis

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

a) the radius of earth

b) the orbital radius

c) the mass of earth

d) the mass of the satellite

Answer:  the radius of earth

Question:

a) v₁ < v₂

b) v₁ = v₂

c) v₁ > v₂

d) None of these

Answer: v₁ < v₂

Question: The escape velocity of a body depends upon mass as

a) m⁰

b) m¹

c) m²

d) m³

Answer: m⁰

Question:  If V_e is escape speed from the earth and V_p is that from a planet of half the radius of earth, then

a)

b)

c)

d) None of these

Answer:

Question: Assertion : If an object is projected from earth surface with escape velocity path of object will be parabola.
Reason : When object is projected with velocity less than escape velocity from horizontal surface and greater than orbital velocity path of object will be ellipse

a) Assertion is correct, reason is incorrect

b) Assertion is incorrect, reason is correct

c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion

d) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

Answer: Assertion is correct, reason is incorrect

Question: When does the object in a satellite escapes to infinity?

a) Both

b) When the total energy is positive

c) When total energy is zero

d) None of these

Answer: Both

Question:  What is the distance of a geostationary satellite from the earth's centre?

a) 4.22 × 10⁴ km

b) 4.22 × 10⁶ km

c) 4.22 × 10⁴ m

d) 4.22 × 10⁶ m

Answer: 4.22 × 10⁴ km

Question:  Select the incorrect statements from the following.
I. The orbital velocity of a satellite increases with the radius of the orbit
II. Escape velocity of a particle from the surface of the earth depends on the speed with which it is fired
III. The time period of a satellite does not depend onthe radius of the orbit
IV. The orbital velocity is inversely proportional to the sequare root of the radius of the orbit.

a) I, II and III

b) I and IV

c) I and II

d) I, II and IV

Answer: I, II and III

Question:  Two satellites of masses m and 2m are revolving around a planet of mass M with different speeds in orbits of radii r and 2r respectively. The ratio of minimum and maximum forces on the planet due to satellites is

a)

b)

c)

d) None of these

Answer:

Question: If suddenly the gravitational force of attraction between earth and a satellite revolving around it becomes zero, then the satellite will

a) move tangentialy to the original orbit in the same velocity

b) become stationary in its orbit

c) move towards the earth

d) continue to move in its orbit with same velocity

Answer: move tangentialy to the original orbit in the same velocity

Question:  A geostationary satellite is orbiting the earth at a height of 5R above that surface of the earth, R being the radius of the earth. The time period of another satellite in hours at a height of 2R from the surface of the earth is

a)

b)

c) 10

d) 5

Answer:

Question:  The mass of a spaceship is 1000 kg. It is to be launched from the earth's surface out into free space. The value of g and R (radius of earth) are 10 m/s² and 6400 km respectively. The required energy for this work will be

a) 6.4 × 10¹⁰ J

b) 6.4 × 10⁸ J

c) 6.4 × 10¹¹J

d) 6.4 × 10⁹ J

Answer: 6.4 × 10¹⁰ J

Question:  For a satellite moving in an orbit around the earth, the ratio of kinetic energy to potential energy is

a)

b)

c)

d) 2

Answer:

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

a) 8 km/sec

b) 10 km/sec

c) 11.2 km/sec

d) 6 km/sec

Answer: 8 km/sec

Question: The moon has a mass of 1/81 that of the earth and a radius of 1/4 that of the earth. The escape speed from the surface of the earth is 11.2 km/s. The escape speed from the surface of the moon is:

a) 2.49 km/s

b) 3.7 km/s

c) 5.6 km/s

d) 1.25 km/s

Answer: 2.49 km/s

Question: A planet in a distant solar system is 10 times more massive than the earth and its radius is 10 times smaller. Given that the escape velocity from the earth's surface is 11 km s^–1, the escape velocity from the surface of the planet would be

a) 110 km s^–1

b) 0.11 km s^–1

c) 11 km s^–1

d) 1.1 km s^–1

Answer:  110 km s^–1

Question:  A satellite revolves around the earth of radius R in a circular orbit of radius 3R. The percentage increase in energy required to lift it to an orbit of radius 5R is

a) 20 %

b) 30 %

c) 40 %

d) 10 %

Answer: 20 %

Question: The escape velocity from the earth's surface is 11 km/s. The escape velocity from a planet having twice the radius and same mean density as that of earth is

a) 22 km/s

b) 5.5 km/s

c) 11 km/s

d) None of these

Answer: 22 km/s

Question: The kinetic energy of a satellite in its orbit around the earth is E. What should be the kinetic energy of the satellite so as to enable it to escape from the gravitational pull of the earth?

a) 2 E

b) 4 E

c) E

d) 3E

Answer:  2 E

Question:  A satellite of mass ‘m’, moving around the earth in a circular orbit of radius R, has angular momentum L. The areal velocity of satellite is (M_e = mass of earth)

a) L /2m

b) L /m

c) 2L /m

d) 3L /m

Answer: L /2m

Question: The radii of circular orbits of two satellites A and B of the earth, are 4R and R, respectively. If the speed of satellite A is 3 V, then the speed of satellite B will be

a) 6 V

b) 12 V

c) 3 V/2

d) 3 V/4

Answer:  6 V

Question:  The least energy required to launch a satellite of mass 100 kg from the surface of a planet of mass M and radius 3200 km in a circular orbit at an altitude of 6400 km is:

a)

b)

c)

d)

Answer:

Question:   A rocket is fired vertically from the surface of mars with a speed of 2 km/s. If 20% of its initial energy is lost due to martian atmosphere resistance, how far will the rocket go from the surface of mars before returning to it? Mass of mars = 6.4 × 10²³ kg, radius of mars = 3395 km, G = 6.67 × 10^–11 Nm²/kg².

a) 1655 km

b) 1155 km

c) 1200 km

d) 1055 km

Answer: 1655 km

Question:  A satellite can be in a geostationary orbit around earth at a distance r from the centre. If the angular velocity of earth about its axis doubles, a satellite can now be in a geostationary orbit around earth if its distance from the centre is

a)

b)

c)

d)

Answer:

Question:

a) –3G Me m/8a

b) –5G Me m/6a

c) zero

d) None of these

Answer: –3G Me m/8a

Question: A satellite is seen after each 8 hours over equator at a place on the earth when its sense of rotation is opposite to the earth. The time interval after which it can be seen at the same place when the sense of rotation of earth and satellite is same will be –

a) 24 hours

b) 8 hours

c) 12 hours

d) 6 hours

Answer: 24 hours

Question:  A satellite is launched in the equatorial plane in such a way that it can transmit signals upto 60° latitude on the earth. The angular velocity of the satellite is

a)

b)

c)

d)

Answer:

Question: The total energy of a circularly orbiting satellite is

a) None of these

b) twice the potential energy of the satellite

c) half the kinetic energy of the satellite

d) twice the kinetic energy of the satellite

Answer: None of these