Gravitational Field

Question 1

Gravitational field

Answer 1

A region of space where a mass experiences a force due to the gravitational attraction of another mass

Question 2

Formula of gravitational field strength

Answer 2

g=Fg/m

Question 3

Point mass

Answer 3

A body covers a very large distance compared to its size

Question 4

Newton’s law of gravitation

Answer 4

The gravitational force between 2 point mass is proportional to the product of the masses and inversely proportional to their separation ²

Question 5

Equation for newton’s law of gravitation

Answer 5

F=Gm1m2/r²

Question 6

Circular orbits in gravitational fields

Answer 6

mv²/r = GMm/r²
V²=GM/r

Question 7

Keplers 3rd law

Answer 7

For planets or satellites in circular orbit about the same central body the square of the time period is proportional to the cube of the radius of the orbit

Question 8

Eq of keplers 3rd law

Answer 8

V=2pir/T
V²=(2pi/r)²
V²=GM/r

Question 9

Geostationary orbit

Answer 9

Remains directly above equator
Moves from west to east
Has on orbital time period same as earth of 24 hours

Question 10

Gravitational field strength eq

Answer 10

Fg=GMm/r²
g=F/m
GMm/r²=gm
g=GM/r²

Question 11

Gravitational potential

Answer 11

The workdone per unit mass in bringing a test mass from infinity to defined point

Question 12

What is the equation of gravitational potential

Answer 12

Gravitational potential = -GM/r

Question 13

Why is gravitational potential negative

Answer 13

Since the potential where r is infinity is defined as zero

Question 14

GPE

Answer 14

The work done in bringing a mass from infinity to that poing

Question 15

GPE

Answer 15

-GMm/r