Term 4 Revision Flashcards
Definition of a Force
Forces are a Push, Pull, or twist… in a particular direction.
What is an unbalanced force
a Change of motion speed and direction.
What is a Balanced force
a constant force or no change is caused to the object if forces cancel each other out.
Explain Air Resistance
For an object falling through the atmosphere, air resistance is the force acting against gravity.
Explain Friction.
Friction is a contact force, it occurs when 2 surfaces are in contact with each other. Friction is a resistance against the movement of an object.
What is gravity?
Gravity is a non-contact force that pulls on an object.
Magnetism is a ….
Non-contact force.
Mass is…
How much matter is inside of you.
Weight is …
measure of the pull of gravity on your mass.
What are Newtons? (N)
Newtons are the way we measure forces.(N)
What Newton’s First law/ Inertia
An object in motion will stay in motion, or an object at rest will remain at rest unless acted upon by an external unbalanced force.
Terminal Velocity is …
A point at when air resistance and gravity are the same and you stop accelerating
Static friction…
Is the friction between stationary objects - bigger.
Kinetic Friction is…
when there is friction between objects that move - smaller.
Wanted Friction
writing on paper.
Unwanted Friction
driving a car when friction is against you.
Explain Buoyancy…
Buoyancyis an upward force (push) by a liquid on an object.
Sinking?
Objects that sink push on a liquid. the object is displacing the liquid or pushes it aside.
what is floating
The liquid pushes back on the object. This is referred to as buoyancy.
If the buoyancy exceeds theweight, then the object floats;
Neutral Buoyancy
If the buoyancy equals the weight, the object hasneutral buoyancy.
What is Density
how muchmassa substance has in a given space.
What is the Formula for density?
D = m/V or density = mass/ volume
Fulcrum
The turning point of a Lever is the Fulcrum.
The Load
The Resistance to motion that a lever works against is the load.
What is the Effort?
The force required to cause the motion is the effort.
What is the Fulcrum?
The turning point of a lever is the fulcrum
What is the Load?
The resistance to motion that a lever works against is the load
What is a 1st class lever?
(EFL)
Fulcrum lies between the effort and the load
e.g. scissors
What is a 2nd class lever?
(ELF)
The load is between the fulcrum and the effort.
The input is always further away from the fulcrum than the output, e.g. Wheelbarrow.
What is a 3rd class lever?
(FEL)
Effort between the fulcrum and the load.
e.g Tweezers or Tongs.
What is a Force multiplier?
1st and 2nd
WHat is a speed multiplier?
3rd
What is a simple machine?
Is when it is used
