Equations

Question 1

What is the equation for work done?

Answer 1

Work done (W, joules) = force (F, neutons) x distance (s, metres)

Question 1

What is the equation for gravitational potential energy?

Answer 1

Eg (energy, joules) = m (mass, kg) x g (gravitational field strength, N/kg) x h (height, Metres)

Question 2

What is the gravitational field strength on Earth?

Answer 2

9.8 n/Kg

Question 3

What is the equation for weight?

Answer 3

W ( weight, neutons) = m (mass, kg) x g (GFS, n/kg)

Question 4

What is the equation for kinetic energy?

Answer 4

Ek ( kinetic energy, joules) = 1/2 x m (mass, kg) x V squared (speed, m/s)

Question 5

The equation for elastic potential energy?

Answer 5

Ee (elastic potent energy, joules) = 1/2 x k (spring constant N/M, x e squared ( extention (m) )

Question 6

What is a spring constant?

Answer 6

A measure of how easy it is to stretch the material.

Question 7

What is the equation for efficiency?

Answer 7

Useful output x 100 (percentage)
/////////////////
Total input

Question 8

How do you calculate total energy input?

Answer 8

Add useful energy output and wasted energy output together

Question 9

How do you calculate power (energy) ?

Answer 9

P (power, watts) = E/t (energy over time, joules and seconds)

Question 10

What is the equation for specific heat capacity?

Answer 10

E triangle = mc triangle theta (energy, joules = mass, kg times specific heat capacity, j/kg times theta, change in temp degrees celcius)

E= mc theta

Question 11

What is the 1st equation for power (voltage)

Answer 11

Power= current x voltage

Watts, amps, volts

Question 12

How do you calculate charge?

Answer 12

Charge (Q) = current (amps) / time (seconds)

Q= I/T

Question 13

How do you calculate the potential difference?

Answer 13

Voltage= current x resistance

V(potent diff) = IxR

Question 14

How do you calculate density?

Answer 14

Density= mass/ volume

P(kg/m2) = M(kg)/V( m2)

Question 15

What is the equation for moment? (Nm)

Answer 15

Moment = force x distance

M=Fxd

Question 16

How do you calculate the force applied to a spring?

Answer 16

Spring constant x extension

Question 17

How do you calculate pressure?

Answer 17

Force / area

Question 18

How to calculate distance travelled?

Answer 18

Speed x time

Question 19

Equation for acceleration?

Answer 19

Change in velocity/ time taken (seconds)

Question 20

How to calculate the resultant force of an object?

Answer 20

Mass (kg) x acceleration

Question 21

Momentum?

Answer 21

Mass x velocity

Question 22

How to calculate wave speed?

Answer 22

Frequency x wavelength

Question 23

What is the equation for power ( current)

Answer 23

Current squared x resistance

Question 24

Equation for energy transferred? (power)

Answer 24

Power x time

Question 25

Energy transferred ( charge)

Answer 25

Charge x potential difference

Question 26

Why is the equation for work done important in physics?

Answer 26

It relates force and distance.

Question 27

If you know the force and distance, how can you calculate the work done?

Answer 27

Equation W=FxS

Question 28

How does the equation for kinetic energy relate to the equation for work done?

Answer 28

They both involve force and distance.

Question 29

What are the steps to calculate total energy imput?

Answer 29

-Useful energy output -Wasted energy output -Add them together

Question 30

What are the factors that effect the equation for power (energy)?

Answer 30

-Energy -time -they are inversley proportional.