Definitions

Question 1

absolute zero

Answer 1

the temperature at which substance has minimum ener

Question 2

specific heat capacity

Answer 2

energy required to raise the temperature of a unit mass of a substance by unit temperature

Question 3

thermal equilibrium

Answer 3

if there is no net heat transfer between two objects

Question 4

latent heat of vaporisation

Answer 4

the energy required to change a liquid into a gas at a constant temperature

Question 5

latent heat of fusion

Answer 5

the energy required to change a solid to a liquid at a constant temperature

Question 6

internal energy

Answer 6

sum of the random kinetic energy and potential energy of molecules in a substance

Question 7

assumptions of the kinetic model of ideal gases

Answer 7

1. elastic collisions with the walls of the container
2. forces between molecules are negligible except during collisions
3. time of collisions much compared to the time between molecules
4. volume of molecules is negligible compared to volume of container

Question 8

Boyle’s law

Answer 8

pressure is inversely proportional to volume for a fixed mass of gas at a constant temperature

Question 9

mole of a substance

Answer 9

6.02x10^23 particles of the substance

Question 10

Newton’s first law

Answer 10

a body will remain at rest or continue to move with constant velocity unless acted on by a force

Question 11

Newton’s second law

Answer 11

the rate of change of momentum is proportional to the net force acting on it in the direction of the force

Question 12

Newton’s third law

Answer 12

when one body exerts a force on another body the other body exerts an equal and opposite force on the first body

Question 13

linear momentum

Answer 13

mass x velocity

Question 14

principle of conservation of linear momentum

Answer 14

total momentum is conserved for a closed system

Question 15

elastic collision

Answer 15

kinetic energy is conserved

Question 16

inelastic collision

Answer 16

where there is some loss of kinetic energy in a collision

Question 17

impulse of a force

Answer 17

force x time for which the force acts

Question 18

gravitational field strength

Answer 18

force per unit mass at a point in a gravitational field

Question 19

Newton’s law of gravitation

Answer 19

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 20

Kepler’s third law

Answer 20

the cube of the distance from the planet to the sun divided by the orbital period squared is the same for all planet’s

Question 21

conditions for circular motion

Answer 21

resultant force acts perpendicular to he velocity

Question 22

geostationary orbit

Answer 22

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

Question 23

radian

Answer 23

53.7 degrees

Question 24

simple harmonic motion

Answer 24

11. acceleration is proportional to the displacement

2. acceleration is directed in the opposite direction the displacement

Question 25

displacement in simple harmonic motion

Answer 25

distance of a body from its equilibrium position

Question 26

amplitude

Answer 26

maximum displacement

Question 27

frequency

Answer 27

the number of oscillations per second

Question 28

angular frequency

Answer 28

measure of the tangential frequency of oscillations

Question 29

phase difference

Answer 29

an angular measurement of how much one oscillation lags or leads another

Question 30

resonance

Answer 30

occurs wen the frequency of oscillation of a driving force is very close to the natural frequency of the driven system; this results in maximum energy transfer to the drive system leading to very large amplitude oscillations