8b P1 astrophysics

Question 1

what is a universe?

Answer 1

is a large collection of billions of galaxies

Question 2

what is a galaxy?

Answer 2

large collection of billions of Stars

Question 3

what is our solar system?

Answer 3

Milky Way galaxy

Question 4

what is weight defined as?

Answer 4

the force acting on an object due to gravitational field strength

Question 5

do planets have strong gravitational field strengths ?

Answer 5

yes

Question 6

what factor effects the gravitational field strength?

Answer 6

the mass, the greater the gas the greater field strength

Question 7

what does a greater field strength mean?

Answer 7

a larger attractive force toward the centre of the planet

Question 8

what does it mean for g to be less strong on a planet?

Answer 8

it would be easier to lift a mass on the surface of the moon than on the earth

Question 9

what changes and what stays the same when g is different?

Answer 9

an objects mass stays the same but the weight will differ depending on the g

Question 10

what does gravitational field strength cause the moon to do?

Answer 10

causes the moon to orbit the sun

Question 11

what does gravitational field strength cause planets to do?

Answer 11

causes planets to orbit the sun

Question 12

what does gravitational field strength cause artificial satellites to do?

Answer 12

causes artificial satellites to orbit the sun

Question 13

what does gravitational field strength cause comets to do?

Answer 13

orbit the sun

Question 14

what are the differences in the orbit of the moon?

Answer 14

• moons orbit the planets in a circular path

- the closer the moon is to the planet the shorter time it will take to orbit and the greater the speed of the orbit

Question 15

what are the differences in the orbit of the comets?

Answer 15

• their orbits are highly elliptical or hyperbolic
• this causes the speed of the comets to change significantly as the distance from the sun changes
• as is gets closer to the sun is increases and as it gets further it decreases

Question 16

what are the differences in the orbit of the planets?

Answer 16

similarities between
- all orbits are slightly elliptical with the sun at one focus
- all orbit in the same plane
- travel the same direction around the sun 
differences 
- orbit at different distances 
- different speeds
- take diff amount of time to orbit

Question 17

what is elliptical?

Answer 17

stretched circles