Definitions

Question 1

define accerleration

Answer 1

the rate of change of velocity.

how much velocity changes every second.

Question 2

define amplitude

Answer 2

maximum displacement from an undisturbed position.

Question 3

define centre of gravity

Answer 3

point through which an object’s weight acts.

Question 4

define charge

Answer 4

a property of electrons and protons.

Question 5

define current

Answer 5

rate of flow of charge.

how much charge flows every second.

Question 6

define displacement

Answer 6

distance from a fixed point.

Question 7

define distance

Answer 7

how far an object has moved.

Question 8

define energy

Answer 8

ability to do something useful.

not created or destroyed but changed from one form to another.

Question 9

define force

Answer 9

a push, pull or twist.

Question 10

define frequency

Answer 10

number of oscillations per second.

Question 11

define gravitational field strength

Answer 11

force on each kilogram due to gravity.

Question 12

define height

Answer 12

vertical displacement.

Question 13

define mass

Answer 13

amount of material in an object.

a massive object is difficult to accelerate.

Question 14

define moment

Answer 14

turning effect of a force.

Question 15

define momentum

Answer 15

mass multiplied by velocity.

conserved in all collisions and explosions.

Question 16

define a period

Answer 16

time taken to make a complete oscillation.

Question 17

define potential difference

Answer 17

energy that each coulomb of charge has.

Question 18

define power

Answer 18

rate that energy is transformed to another form.

number of joules transformed every second.

Question 19

define pressure

Answer 19

force per unit area.

Question 20

define radiation

Answer 20

waves or particles that are emitted from a substance.

Question 21

define radioactivity

Answer 21

ability of a substance to emit waves or particles.

Question 22

define resistance

Answer 22

ability to reduce electrical current.

Question 23

define velocity

Answer 23

speed in a certain direction.

Question 24

define wavelength

Answer 24

distance between one crest and the next crest.

Question 25

define weight

Answer 25

force due to gravity.