Forces and Speed Flashcards
What is a force?
A push or a pull
What force pulls me down to earth?
Weight
What force keeps boats and other objects afloat?
Upthrust
What is the formula for calculating weight?
Weight=mass x gravitational field strength
Is weight a force?
Yes
What is weight measured in?
Newtons (N)
What is mass measured in?
Kilograms (kg)
What are 3 characteristics of a streamlined shape?
1) rounded front
2) slowly tapering tail
3) smooth shape with no projections
What are two ways to reduce friction?
1) Lubrication
2) Streamlining
What is the formula for calculating density?
Density=mass/volume
What is the formula for calculating speed?
Speed=distance/time
What is mass?
The amount of matter a thing is made up of
What is friction?
The force that resists movement because of contact between two surfaces
What does it mean if something is streamlined?
If something is streamlined it is shaped to reduce resistance to motion from air or water
What is weight?
The force of the Earth on an object due to its mass
What is a newton meter?
A piece of equipment used to measure weight in newtons
Can you give 3 examples when friction is useful?
There are many e.g. brakes, matches and even walking
What is the formula for time?
Time=distance/speed
What does compress mean?
To squash into a smaller space
What is lubrication?
A substance that reduces friction between surfaces when they rub together
What is the definition of a driving force?
The force that is pushing or pulling something
What happens if something deforms?
It changes shape
