Topic 8 (planetary Motion And Gravity)

Question 1

What is Kepler’s first law

Answer 1

The planets move in an elliptical orbit around the sun

Question 2

What is the perihelion and aphelion

Answer 2

Closest and furthest points from the the sun in a planets orbit

Question 3

What is the apogee and perigee

Answer 3

The point at which an object is furthest or closest to the earths centre

Question 4

What is Kepler’s second law

Answer 4

States that an object is travelling fastest when nearest to its perihelion and slowest at the aphelion

Question 5

What is Kepler’s 3rd law

Answer 5

T2/R3 = a constant

Eg. T. R. T2. R3
P1.0.7 2. 0.49. 8. 0.49/8=k=0.06125
P2. ? 5. ?*2 25

T2 = kR3=0.06125 x 125 = 7.65625 = ?*2

? = 2.77

Question 6

What is stated by newton’s universal law of gravitation

Answer 6

Every body in the universe attracts every other body with a force directly proportional to its mass and inversely proportion to the square of their distance apart (separation)