GRAVITAION

Question 1

Gravitational force is ……..

Answer 1

weak, attractive, and conservative

Question 2

Gravitational force obeys what law

Answer 2

inverse square law

Question 3

The formula of G force

Answer 3

F=GMm/R^2

Question 4

Value of Universal Gravitational constant

Answer 4

6.67 X 10^-11

Question 5

Acceleration due to gravity with HEIGHT

Answer 5

g’ = g(1-2h/R)

g’ = g/(1-h/R)^2

Question 6

Acceleration due to gravity with DEPTH

Answer 6

g’= g(1-D/R)

Question 7

Gravitational PE

Answer 7

PE = -GMm/R

Question 8

Escape Velocity of Earth

Answer 8

11.2 km/s

Question 9

Escape Velocity formula

Answer 9

EV = (2GM/R+h)^1/2

Question 10

Orbital Velocity formula

Answer 10

OV = (GM/R+h)^1/2

Question 11

Relation b/w Kinetic, potential and total energy

Answer 11

TE = -KE = PE/2

Question 12

Angular momentum in planetary motion is

Answer 12

Conserved

Question 13

Types of satellite

Answer 13

Geostationary and Polar satellite

Question 14

The time period for Geostationary satellite and polar satellite

Answer 14

24 hours and 100 minutes

Question 15

Distance from Earths surface GS & PS

Answer 15

35800 km & 800 km

Question 16

When is weightlessness experienced

Answer 16

Normal reaction = 0

Question 17

Kepler’s first law

Answer 17

LAW OF ORBITS
The planet revolves around the sun in an elliptical orbit with the sun at one of the foci of the ellipse.

major axis (2a)
minor axis (2b)

Perihelion (perigee): Max KE, least PE, closest to sun
Aphelion (apogee): Least KE, max PE, furthest from sun

Essentricity(e) = (Distance of sun from origin of axis)/semimajor axis

Question 18

Second law

Answer 18

LAW OF AREAS

If net torque=0, equal area swept in equal time intervals

Question 19

Third law

Answer 19

LAW OF PERIODS

Square of the time period for on rev is cube of semi major axis

Question 20

Gravitational Potentiol

Answer 20

V = U/m = -GM/r

Question 21

areal velocity and angular momentum relation

Answer 21

aV = L/2m

Question 22

interstellar velocity

Answer 22

v^2 = u^2 - Ve^2

v= interstellar veloctiy
u= velocity with which body leaves planet 
Ve= escape velocity

Question 23

If radius decreases by factor of n then time period

Answer 23

T’ = T/n

Question 24

gravitational field inside a shell

Answer 24

0

Question 25

gravitational field outside a shell

Answer 25

Gm/r^2

Question 26

gravtaional field inside a solid sphere

Answer 26

Gmr