Astronomy

Question 1

What is Kepler’s First Law?

Answer 1

Planets move in elliptical orbits with the Sun at one focus.

Question 2

What is Kepler’s Second Law (Law of Equal Areas)?

Answer 2

A line from a planet to the Sun sweeps out equal areas in equal times → planets move faster when closer to the Sun (perihelion) and slower when farther (aphelion).

Question 3

What is Kepler’s Third Law (Harmonic Law)?

Answer 3

The square of a planet’s orbital period (P²) is proportional to the cube of its average distance from the Sun (a³).

Question 4

Who formulated the law of universal gravitation?

Answer 4

Isaac Newton.

Question 5

What is Newton’s Law of Universal Gravitation?

Answer 5

Every two masses attract each other with a force proportional to the product of their masses and inversely proportional to the square of their distance.

Question 6

How does gravitational force change with distance?

Answer 6

It decreases with the square of the distance (inverse-square law).

Question 7

What is a Lagrange point?

Answer 7

A position in space where the gravitational pull of two large bodies balances the centripetal force felt by a smaller object.

Question 8

How many Lagrange points are there in a two-body system?

Answer 8

Five (L1 through L5).

Question 9

Which Lagrange points are stable?

Answer 9

L4 and L5 (60° ahead and behind the smaller body in its orbit).

Question 10

Give one use of Lagrange points in space exploration.

Answer 10

Telescopes at L2 (e.g., James Webb Space Telescope) for a stable, unobstructed view of space.