G484 Definitions

Question 1

State the principle of conservation of momentum

Answer 1

Within a closed system, the total momentum in any specified direction remains constant.

Question 2

Define what is meant by a perfectly elastic collision

Answer 2

In a perfectly elastic collision, momentum, kinetic energy and total energy are all conserved.

Question 3

Define linear momentum

Answer 3

Momentum = Mass x velocity

Question 4

Define what is meant by an Inelastic collision

Answer 4

In an Inelastic collision, both momentum and total energy are conserved but the kinetic energy is not conserved as its transformed to other types of energy

Question 5

Define Newton’s law of gravitation

Answer 5

Two point masses attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of their separation.

Question 6

Define Kepler’s third law of planetary motion

Answer 6

The square of the period T of a planet is directly proportional to the cube of its distance r from the sun.

Question 7

Define gravitational field strength

Answer 7

The gravitational force exerted per unit mass on an object at a point within the field.

Question 8

Define orbital period of a satellite

Answer 8

The time taken for one orbit.

Question 9

Define geostationary orbit

Answer 9

The orbit of an artificial satellite which has a period equal to one day, and is in the same direction as planetary rotation, so the satellite remains over the same point on the Earth’s equator.

Question 10

Define Free Oscillation

Answer 10

The natural oscillation of an object after an initial disturbance

Question 11

Define Forced Oscillation

Answer 11

The oscillation of an object due to a driving frequency

Question 12

Define Natural Frequency

Answer 12

The frequency at which an object oscillates freely

Question 13

Define Oscialltion

Answer 13

The repeated movement of an object back and forth about an equilibrium

Question 14

Define Amplitude

Answer 14

The maximum displacement of an oscillation

Question 15

Define Period

Answer 15

The time taken for one complete oscillation

Question 16

Define Frequency

Answer 16

The Number of full oscillations per unit time

Question 17

Define Phase Difference

Answer 17

The difference in Phase between two oscillations with the same frequency, measured in Radians

Question 18

Define Simple Harmonic Motion (S.h.m)

Answer 18

A type of oscillation for which the mass always accelerates towards the equilibrium at a rate directly proportional to it’s displacement at that point.

Question 19

What unit does impulse have?

Answer 19

Ns or kgms-1

Question 20

The two forces cause by Newton’s 3rd law must…

Answer 20

Act on different bodies
Be equal in magnitude
Be opposite in direction
Be of the same type

Question 21

What is a special case of Newton’s second law where mass remains constant?

Answer 21

F=ma

Question 22

Which part of a force against time graph shows impulse?

Answer 22

The area under the graph

Question 23

Impulse =

Answer 23

The change of momentum

Question 24

What is Newtons third Law?

Answer 24

When two bodies interact, the forces they exert on each other are equal and opposite

Question 25

What is Newton’s second Law?

Answer 25

The net force acting on an object is equal to the rate of change of linear momentum of the object. The net force and change in momentum are in the same direction

Question 26

What is Newton’s first Law?

Answer 26

An object will remain at rest or remain at constant velocity, unless it is acted upon by an external force

Question 27

Define the period

Answer 27

The time taken for one complete oscillation

Question 28

Define centripetal acceleration

Answer 28

The acceleration towards the centre of the circle that holds the object in elliptical orbit a=v²/r

Question 29

Define centripetal force

Answer 29

The net force acting on an object describing a circular path. It is always directed towards the centre of the circle

Question 30

Define the radian

Answer 30

One radian is the angle subtended at the centre of a circle by an arc of length equal to the radius of the circle

Question 31

Define specific latent heat

Answer 31

The energy required per kilogram of the substance to change its state without a change in temperature

Question 32

Define specific heat capacity

Answer 32

Energy supplied
______________________
Mass x Temperature change

Question 33

Define specific latent heat of vaporisation

Answer 33

The energy required to boil a substance at constant temperature

Question 34

Define latent heat of fusion

Answer 34

The energy required to melt a substance at constant temperature

Question 35

Define internal energy

Answer 35

The sum of the random distribution of kinetic and potential energies of molecules in a closed system

Question 36

State the relationship between the temperature and kinetic energy of an atom

Answer 36

The mean kinetic energy of an atom of an ideal gas is proportional to the thermodynamic temperature.

Question 37

State Charles’ law

Answer 37

For a constant pressure, the volume is directly proportional to the temperature of the gas

Question 38

State Boyle’s law

Answer 38

The pressure exerted by a fixed mass of gas is inversely proportional to its volume, as long as temperature is constant

Question 39

Define a mole of a substance

Answer 39

One mole of any substance is the amount of that substance that contains the same number of particles as there are in 12g of carbon 12

Question 40

What is a damped oscillation?

Answer 40

An oscillatory motion where the amplitude decreases with tme due to energy loses

Question 41

What is resonance?

Answer 41

Resonance is when the forced motion acting on an oscillator has a frequency which matches the oscillators natural frequency.