2. Content
Introduction to Rockets
History of Rocket
Principle behind Rocket
Types of Fuel used
Launching a Satellite
Difference between Rocket & Satellite
Application
4. History of Rocket
The Chinese is claimed by many to be the inventor
of the black powder (about 200 B.C – 2216 Years
back) and thus the rockets
India should be honored instead of China for the
Rocket Crackers during Diwali & Temple Festivals
5000 Year old Tradition
5.
6. Contd.
The Chinese also developed rockets and flame
torches to be used in combat against their main
enemy, the Mongols.
10. A balloon is a simple example
of a rocket.
Rubber walls compress
the air inside. Air
escapes from the small
opening at one end and
the balloon flies.
11. Action and Reaction
A rocket takes off only when it
expels gas.
Action: The rocket pushes the
gas out of the engine.
Reaction: The gas pushes up
on the rocket.
UP
DOWN
12. DRAG-Opposing Force
DRAG = Air Resistance
Air Resistance causes friction which
slows down the Rocket. Friction
always works in the opposite direction
of the Rocket’s motion.
(Even when a rocket is descending,
drag counteracts the rocket’s motion!)
UP
DOWN
Air Resistance
(DRAG)
MOTIO
N
(Reactio
n)
MASS
EXITING
(Action)
13. TIPS: REDUCING DRAG
More
AERODYNAMIC or
pointed nose cone: This
causes the air to “part”
around the bottle.
More Aerodynamic
fins:
Thinner, more streamlined
fins reduce drag. Position
fins toward the tail of the
rocket (moves CP!).
A Round or Contoured
Nose Cone allows Air to
easily separate, thus reducing
the effects of Drag
Drag has a significant
effect on blunted bodies,
such as the Nose Cone
below.
14. Rocket Fin Shapes
Square/Trapezoidal Fins yield MORE stability, but create MORE drag.
Triangular/ Epsilon Fins introduce LESS drag, but yield LESS stability.
15. Thrust
Forward motion or
thrust can best be
described by observing a
balloon filled with air.
When air is released
from the balloon, forces
inside the balloon cause
it to move to the left.
16. The Action (Thrust) has to be greater than
the weight due to gravity of the rocket for
the reaction (liftoff) to happen.
17. Weight
Weight is the force generated by the
gravitational attraction on the rocket.
More the Weight more the Thrust required to
push
18. Lift
The lift force (the aerodynamic force
perpendicular to the flight direction) is used
to overcome the weight.
On a rocket, thrust is used in opposition to
weight.
On many rockets, lift is used to stabilize and
control the direction of flight.
19. Stability During Flight
The purpose of
putting fins on a
rocket is to provide
stability during
flight, that is, to
allow the rocket to
maintain its
orientation and
intended flight
path.
20. Stability During Flight…
Think about a dart…
Fins or feathers in the
rear act like wind veins
and trail behind.
Heavy mass made of
metal carriers the
momentum.
21. Type of Fuel Used
Solid Fuel Rocket
Liquid Fuel Rocket
Water Pressure Rocket
22. Solid Fuel Rockets
Fuel in solid form burns and is
converted to hot gasses.
Hot gasses expand and create high
pressure.
Pressure escapes out nozzle, pushing
against air and rocket body equally.
23. More on Solid Fuel Rockets
Solid-fueled rockets
use a fuel and
oxidizer in solid
form.
The fuel and
oxidizer are in a
powdery or rubbery
mixture known as
the grain or charge.
24. Once a solid-fueled
rocket is ignited, it
burns completely.
There is no way to
stop the combustion
or to change the
amount of thrust.
More on Solid Fuel Rockets
25. Liquid Fuel Rockets
Work on same basic principles as solid
fuel.
Carry liquid fuel and oxygen.
Unlike solid fuel, liquid fuel can be
regulated to control thrust.
26. … Liquid Fuel
Used for launches and interplanetary travel,
liquid fuel rockets
More versatile than solid rockets because the
amount of thrust can be controlled, but they are
less reliable than solid rocket engines.
27. Water Rockets
Instead of hot gasses creating pressure, we
use a bike pump and store pressure.
Action: Expelling water from engine bottle
(water is forced down)
Reaction: Water resisting against rocket
body (Rocket is forced up)
31. Propulsion
All spacecraft need to reach about 17,500 miles per
hour to get into orbit.
Thrust is used to push the spacecraft this fast.
Thrust is produced by burning a rocket fuel with
oxygen.
If there is not enough thrust the spacecraft will fall
back to earth due to gravity.
32. Fixing a Satellite in an Orbit
How fast is this? R ~ 6400 km = 6.4106 m,
so you’d need a speed of
sqrt[(6.4106m)(10m/s2)] = sqrt (6.4107)
m/s, so:
v 8000 m/s = 8 km/s = 28,800 km/hr ~
18,000 mph
42. Difference between rockets and
satellite
Rockets Satellite
Rockets are powered by their
own motors with fuel tanks,
usually going up unless there
is a malfunction.
Satellites, on the other hand,
are powered by gravity's
inertia and usually solar
power with small guidance
boosters to keep them in
orbit for longer periods.
Rockets carry the satellites Satellites orbit while rockets
go up.
Satellites orbit a planetary
body, such as the Earth or
moon, or any other object in
space.
43. How many satellites are
in orbit?
There are approximately 9,000.
At the time of this writing, there were
8,953 satellites in orbit around Earth
including 4,503 larger pieces of space
junk.
44. What’s the path of the satellite?
Geosynchronous orbit -- Circle
45. What do you mean by natural and artificial
satellite?
Artificial satellites are man made while natural
satellite are formed by nature.
Artificial satellites need energy for installation and to
rotate around any planet while natural satellites do
not require any energy for revolving.
Artificial satellites move closer than the natural
satellite. Some examples are weather satellites
(GOES), communication satellites (ANIK),
navigation satellites (GPS), scientific satellites
(TERRIERS), and military satellites (MILSTAR).
46. Moon is a natural satellite and the earth can also be
considered a satellite of the sun are examples of
natural satellite.
What do you mean by natural and artificial
satellite?
47. How long it will take for a satellite to get into its
orbit?
Depends on where in space and the speed of the
aircraft … The shortest trip to the Moon took place in
January 2006 by the NASA Pluto probe New
Horizons. With the speed of 58,000 km/hr, it only
took 8 hours and 35 minutes to get to the Moon from
Earth. Apollo missions took about three days to
reach the moon. It will take minimum 6 hrs to reach
international space station
48. What is the life span of satellite?
Around Ten years
49. What will happen to the debris of rocket?
Most everything that does fall back to the earth
burns up in the atmosphere upon reentry. This is
because of the friction generated by the atmosphere
on the debris.
50. How many launch pads are in India?
Four
Vikram Sarabhai Space
Centre,thiruvananthapuram,thumba
Balasore,odisha
Satish Dhawan Space Centre, Sriharikota, Andhra
Pradesh
Abdul Kalam Island, Odisha
51. Does the time of flight vary with the altitude?
Yes
52. What’s the distance between the earth and the
orbit?
Geostationary orbit, geostationary earth
orbit or geosynchronous equatorial orbit
(GEO) is a circular orbit 35,786 kilometres
(22,236 mi) above the earth's equator . satelite's
in high geostationary orbits 23,000 miles about
37,000km are beyond the van allen radiation belt
Low earth orbit which is a satelite orbiting below
2000 km between the radiation belt and the earths
atmosphere.
53. Why launch pads are located near seashore?
The launching stations are generally located near
eastern coast line so that, just in case of failure of the
launch, the satellite does not fall on built-up
hinterland.
54. Uses of Rocket
Military
Satellite Launch
Science and research
Spaceflight
Rescue
