1. Geocentric orbits with
altitudes up to 2,000
2. Pick
the correct option:
[A] All geostationary orbits are also
geosynchronous, but not all geosynchronous orbits are geostationary.
[R] A geostationary orbit stays exactly above the
equator, whereas a geosynchronous orbit may swing north and south to cover more
of the Earth's surface.
(a)
both the statements are correct and correct
explanation
(b) both the
statements are correct and does not explanation the statement
(c)
[A] is correct but [R] is wrong
(d)
[A] is wrong but [R] is correct
3.
An elliptical orbit used to transfer
between two circular orbits of
different altitudes, in the same plane-
(a)
bi-elliptic transfer
(b) Hohmann transfer
(c)
Low energy transfers
(d)
All of these
4.
What
is/are the condition followed for Gravity-free Drag-free Space Flight
(a)
Far
away from any massive body ⇒no gravity
(b)
Far
away from any sensible atmosphere ⇒no aerodynamic
forces
(c)
Only
force applied is from rocket motor
(d) All of the above
5.
Forces acting on a vehicle in the
atmosphere will be
(a)
Gravity
(b)
Aerodynamic force
(c)
Thrust
(d) All of the above
6.
Thrust – to – weight ratio for Large
surface launched vehicles:
(a) 1.2-2.2
(b)
5.4-6.8
(c)
10-50
(d)
50-100
7.
Thrust – to – weight ratio for Small
missiles:
(a)
1.2-2.2
(b)
5.4-6.8
(c)
10-50
(d) 50-100
8.
For
a vehicle in gravitation-less space, to boost the vehicle velocity by 1500
m/sec, if the effective motor exhaust velocity is 2100 m/sec. If the initial
total vehicle mass is 4400 kg, the corresponding propellant masses
(a)
220.3
kg
(b)
899.7
kg
(c)
2151.6
kg
(d)
2246.1
kg
9.
Compute
the propellant mass required to a mission orbit requiring a velocity impulse of
4400 m/s. Assume that the burnout mass of the rocket structure is 2000 kg and
that the specific impulse of the propellant (LO2/LH2) and rocket motor
combination is 460 sec.
(a)
330.5
kg
(b)
530.5
kg
(c)
3305
kg
(d)
5305
kg
10.
For
an elliptical orbit,
(a)
Perigee velocity is equal to apogee.
(b)
Perigee
velocity is less than apogee.
(c) Perigee velocity is greater than apogee.
(d)
perigee
velocity does not affect apogee
11.
If 0°≤i<90°, the satellite
orbits in the same direction as the earth’s rotation (orbiting eastward around
the earth)
(a)
equatorial orbits
(b) prograde orbit.
(c)
retrograde orbit
(d)
Polar orbits
12.
If 90°<i≤180°, the satellite
orbits in the opposite direction of the earth’s rotation (orbiting westward
about the earth)
(a)
equatorial orbits
(b)
prograde orbit.
(c) retrograde orbit
(d)
Polar orbits
13.
Consider an initial circular, LEO at a 200km.What
velocity would be required to produce an elliptical orbit with a 200km altitude
at periapsis and 2000km altitude at apoapsis?[RE= 6400km]
(a) 0.45
(b)
0.54
(c)
0.62
(d)
0.77
14.
What will be the sign change when the velocity
added to a spacecraft initial velocity changed from the initial to final orbit?
(a)
Zero
(b)
Positive
(c)
Negative
(d) Positive or negative
15.
Considering a circular Mars orbit of radius 8000km
to an apogee orbit radius 15000 km. The time for transfer is [Take:-
]
(a)
0.26 hr
(b)
1.04 hr
(c)
5.2 hr
(d) 10.4 hr
16.
A spacecraft launched from a circular orbit of
radius 9100km to a final coplanar, elliptical orbit with eccentricity of 0.1
and perigee radius of 9000 km.[
.
A.
The flight path angle on the final orbit is-
(a) 2.508 deg
(b)
– 2.508 rad-1
(c)
28.464 deg
(d)
331.536 rad-1
B.
The velocity change necessary to convert from the
initial to the final orbit(in km/s)
(a)
0.292
(b) 0.416
(c)
0.618
(d)
0.910
17.
Which of the following statement is correct for a
Hohmann transfer between two circular coplanar orbits?
(a)
The apoapsis radius equal to radius of the initial
orbits and the periapsis radius equal to radius of the final orbit.
(b) The periapsis radius equal to radius of the initial
orbits and the apoapsis radius equal to radius of the final orbit.
(c)
The periapsis radius less than radius of the
initial orbits and the apoapsis radius equal to radius of the final orbit.
(d)
The apoapsis radius equal to radius of the initial
orbits and the periapsis radius greater than radius of the final orbit.
18.
Pick the appropriate option , according to the
corresponding propellant with an
increasing Specific Impulse
(a)
Nitric acid/mono-methyl-hydrazine < Cold Gas
< Mono-propellant-hydrazine < LO2/LH2
(b)
Mono-propellant-hydrazine < Cold Gas <
LO2/LH2 < Nitric acid/mono-methyl-hydrazine
(c) Cold Gas < Mono-propellant-hydrazine < Nitric
acid/mono-methyl-hydrazine < LO2/LH2
(d)
Mono-propellant-hydrazine < Cold Gas < Nitric
acid/mono-methyl-hydrazine < LO2/LH2
19. If
the wedge half angle θ is greater than θmax , the shock becomes
(a) Oblique
shock
(b) Normal
shock
(c)
Bow
shock
(d) Expansion
shock
20.
An
incompressible fluid flows over a flat plate with zero pressure gradients. The
boundary layer thickness is 1mm at a location where Reynolds number is 1000.If
the velocity of the fluid alone is increased by a factor of 4, then the
boundary layer thickness at the same location , in mm will be
(a)
0.25
(b) 0.5
(c)
2
(d)
4
