Gravitational field

Question 1

Gravitational force is always ________.

Answer 1

Gravitational force is always attractive

Question 2

What is a force field?

Answer 2

A force field is a region in which a body experiences a force.

Question 3

What object has gravitational fields?

Answer 3

only large mass have gravitational field that produce a significant effect.

Question 4

what is a radial field?

Answer 4

The lines of force meet at the centre of the point mass

Question 5

What does it mean when a field has high line density?

Answer 5

The higher a line density is, the stronger a gravitational field.

Question 6

what happen to the field lines when it is close to earth’s surface?

Answer 6

the field is almost uniform - the field lines are almost parallel.

Question 7

what does gravitational force depend on?

Answer 7

the masses and the distance between them

Question 8

what is gravitational force?

Answer 8

F=Gm1m2/r^(2)

Question 9

what is inverse square law?

Answer 9

F is proportional to 1/r^(2)

Question 10

what happen to the force when the distance between two masses increases?

Answer 10

the force decreases

Question 11

what happen to the force if the distance is double?

Answer 11

the force will be one quarter the strength of the original force

Question 12

why the law of gravitation is an inverse square law?

Answer 12

because the gravitational field is radial

Question 13

what is gravitational field strength?

Answer 13

g=F/m

Question 14

what does gravitational field strength tell you?

Answer 14

it tells you how strong the force due to gravity is at any point in a gravitational field

Question 15

what is the unit for g?

Answer 15

Nkg^(-1)

Question 16

is g a vector quantity or scalar quantity?

Answer 16

vector and it always point towards the centre of mass of the object whose field you are describing.

Question 17

what would you describe g at Earth’s surface?

Answer 17

it’s almost constant

Question 18

radial field

Answer 18

g=GM/r^(2)

Question 19

what is gravitational potential?

Answer 19

V=-GM/r

Question 20

what is the unit for gravitational potential?

Answer 20

Jkg^(-1)

Question 21

what does gravitational potential tell you?

Answer 21

gravitational potential is the gravitational potential energy that a unit mass would have

Question 22

why is gravitational potential negative?

Answer 22

Gravitational potential is negative at the surface of the mass and increases with the distance from the mass

Question 23

g=?

Answer 23

• delta V/ delta r

Question 24

what is gravitational potential difference?

Answer 24

delta W = m delta V

Question 25

what does gravitational potential difference tell you?

Answer 25

it's the energy needed to move a unit mass and it depends on the mass and the gravitational potential difference you move it through

Question 26

what is gravitational potential energy

Answer 26

Ep = mV = -GMm/r

Question 27

What does gravity act like to objects in orbit?

Answer 27

Gravity acts as the centripetal force that keeps objects in orbit around a much larger body

Question 28

What keep planets and satellites in orbit?

Answer 28

Gravitational force

Question 29

what is the speed of satellites?

Answer 29

V^(2)=GM/r

Question 30

what is the speed of satellites proportional to?

Answer 30

V is proportional to 1/r^(1/2)

Question 31

What is orbital period?

Answer 31

T= (4pi^(2)r^(3)/GM)^(1/2)

Question 32

what is the definition of orbital period?

Answer 32

the time taken for a satellite to make one orbit

Question 33

What is orbital period proportional to?

Answer 33

T is proportional to (r3)^(1/2) | The greater the radius, the slower it will travel and the longer it will take to complete one orbit

Question 34

When a satellite travels in a circular orbit, does the total energy change?

Answer 34

No, It remains constant

Question 35

what forms of energy does a satellite have when it is travelling?

Answer 35

potential energy and kinetic energy

Question 36

When a satellite travels in a circular orbit, does kinetic energy change?

Answer 36

No, It remains constant

Question 37

When a satellite travels in a circular orbit, does potential energy change?

Answer 37

No, It remains constant

Question 38

When a satellite travels in a elliptical orbit, does the total energy change?

Answer 38

No, It remains constant

Question 39

When a satellite travels in a elliptical orbit, would kinetic energy change?

Answer 39

Yes, it increases when the potential energy decreases. in other words, it speeds up as its height decreases

Question 40

When a satellite travels in a elliptical orbit, would potential energy change?

Answer 40

Yes, it increases when the kinetic energy decreases. It slower down as height increases.

Question 41

what is a geosynchrpnous satellite?

Answer 41

it's a satellite orbits directly over the equator and it's stationary relative to a certain point on the Earth