Unit 4- Gravity, Orbits, Circular Motion and Simple Harmonic motion

Question 1

Newton’s law of Gravitation

Answer 1

The gravitational force between two masses is proportional to the product of the masses and inversely proportional to the square of the distance between them

Question 2

Keepler’s third law

Answer 2

The cube of the planets distance from the Sun divided by the square of the orbital period is the same for all planets

Question 3

Conditions for circular motion

Answer 3

Resultant force acts perpendicular to the velocity

Question 4

Geostationary orbit

Answer 4

An equatorial orbit with a period equal to the rotation period of the earth and in the same direction

Question 5

Radian

Answer 5

2 Pi radians = 360 degrees

Question 6

Simple Harmonic motion

Answer 6

1. Acceleration is proportional to displacement

2. Acceleration is directed in the opposite direction to the displacement

Question 7

Displacement (in SHM)

Answer 7

Distance of a body from its equilibrium position

Question 8

Amplitude

Answer 8

Maximum displacement

Question 9

Gravitational field strength

Answer 9

Force per unit mass at a point in a gravitational field

Question 10

Frequency

Answer 10

Number of oscillation per second

Question 11

Angular frequency

Answer 11

2Pi x frequency or 2Pi/T

Question 12

Phase difference

Answer 12

An angular measure of how much one oscillation leads or lags another oscillation

Question 13

Resonance

Answer 13

When the frequency of oscillation of the driving force is very close to the natural frequency of the driven system. Resulting is maximum energy transfer to the driven system, leading to very large amplitude oscillation