Motion Math
A car travels 20 m in 4 s.
What is the speed?
v=d/t
v = 20 / 4
5 m/s
What is the equation for work?
W = Fd
What is the equation for weight?
W = mg
What does amplitude measure?
Wave height / energy
A wave bounces off a surface.
Reflection
An object changes velocity from 2 m/s to 10 m/s in 4s. Find acceleration.
a=(vf−vi)/t
a = (10 − 2) / 4
2 m/s²
A force of 12 N moves an object 5 m. Find work.
W = 12 × 5
60 J
Find the weight of a 6 kg object on Earth.
W = 6 × 9.8
58.8 N
What is the equation for wave speed?
v = fλ
A wave bends when entering a new medium.
Refraction
A runner moves east at 6 m/s.
What makes this velocity instead of speed?
Direction
What is the equation for power?
P = W/t
Which changes on the Moon: mass or weight?
Weight
A wave has:
frequency = 5 Hz
wavelength = 2 m
Find speed.
v = 5 × 2
10 m/s
A wave spreads out after passing through an opening.
Diffraction
A runner moves 8 m/s west. Is this speed or velocity?
Speed because it has a direction
A machine does 200 J of work in 4 s. Find power.
P = 200 / 4
50 W
An object weighs 98 N. Find the mass.
m = 98 / 9.8
10 kg
If frequency increases and speed stays constant, what happens to wavelength?
Wavelength decreases
Wave energy is taken into a material instead of reflecting.
Absorption
A train travels 200 m in 20 s. Find speed.
10 m/s
A machine produces 100 W of power for 10 s. How much work is done?
W = Pt
W = 100 × 10
1000 J
An astronaut has a mass of 75 kg. Find their weight on Earth.
W = 75 × 9.8
735 N
Which wave carries more energy?
Wave A: small amplitude
Wave B: large amplitude
Wave B
Two waves overlap and combine to form a larger or smaller wave.
What is this phenomenon called?
Interference