equations

Question 1

What is the equation for efficiency?

Answer 1

useful energy(or power) transferred
divided by
total energy supplied

Question 2

What is the equation for Power?

Answer 2

work done
divided by
time

Question 3

What is the equation for kinetic energy?

Answer 3

1/2 x mass x speed(or velocity)squared

Question 4

What is the equation for work done?

Answer 4

work done=force x distance

Question 5

disntance travelled=

Answer 5

average speed x time

Question 6

acceleration=

Answer 6

change in velocity divided by the time taken

Question 7

force=

Answer 7

mass x acceleration

Question 8

weight=

Answer 8

mass x gravitational field strength

Question 9

momentum=

Answer 9

mass x velocity

Question 10

change in gravitational potential energy=

Answer 10

mass x gravitational field strength x change in vertical height

Question 11

kinetic energy =

Answer 11

1/2 x mass x (speed)*2

Question 12

efficiency=

Answer 12

useful energy transferred by the device/total energy supplied to the device

Question 13

wave speed=

Answer 13

frequency x wavelength

Question 14

wave speed=

Answer 14

distance/time

Question 15

work done=

Answer 15

force x distance moved in the direction of the force

Question 16

power=

Answer 16

work done/time taken

Question 17

energy transferred=

Answer 17

charge moved x potential difference

Question 18

charge=

Answer 18

current x time

Question 19

potential difference=

Answer 19

current x resistance

Question 20

second equation for power ?

Answer 20

power = energy transferred/time taken

Question 21

electrical power=

Answer 21

current x potential difference

Question 22

second electrical power equation

Answer 22

electrical power = (current)*2 x resistance

Question 23

density=

Answer 23

mass/ volume

Question 24

force exerted on a spring

Answer 24

spring constant x extension

Question 25

(final velocity)*2 -(initial velocity)*2 =

Answer 25

2 x acceleration x distance

Question 26

force=

Answer 26

change in momentum/time

Question 27

energy transferred=

Answer 27

current x potential difference x time

Question 28

force on a conductor at right angels to a magnetic field carrying a current=

Answer 28

magnetic flux density x current x length

Question 29

For transformers with 100% efficiency,potential difference across primary coil x current in primary coil=

Answer 29

potential difference across secondary coil x current in secondary coil

Question 30

change in thermal energy =

Answer 30

mass x specific heat capacity x change in temperature

Question 31

thermal energy for a change of state=

Answer 31

mass x specific latent heat

Question 32

energy transferred in stretching=

Answer 32

0.5 x spring constant x (extension)*2