Paper 1 Equations

Question 1

Average speed =

Answer 1

distance/time

Question 2

acceleration =

Answer 2

change in velocity/time taken

a = (v-u)/t

Question 3

resultant force =

Answer 3

mass x acceleration

F = m x a

Question 4

weight =

Answer 4

mass x gravitational field strength

W= m x g

Question 5

momentum =

Answer 5

mass x velocity

p = m x v

Question 6

Change in gravitational potential energy =

Answer 6

mass x gravitational field strength x change in height

ΔGPE = m x g x Δh

Question 7

Kinetic energy =

Answer 7

1/2 x mass x speed squared

KE = 1/2 x m x v^2

Question 8

Efficiency =

Answer 8

useful energy output/total energy input

or

useful power output/total power input

(expressed as a decimal or x100 to express as a percentage)

Question 9

Wave speed =

(there are two!)

Answer 9

frequency x wavelength

v = f x λ

or

distance/time

v = x/t

Question 10

In the equation v2 - u2 = 2ax What do v and u stand for?

Answer 10

v = final velocity in m/s
u = initial velocity in m/s

Question 11

What is the equation
F=(mv-mu)/t expressed in words?

Answer 11

Force is equal to rate of change of momentum.

Question 12

Referring to the relationship
F=(mv-mu)/t
What will be the impact on F if you increase t?

Answer 12

Increasing t reduces F

Reducing momentum over an extended period of time reduces the resultant force felt.