P2- Forces Flashcards
What does a vector quantity have?
Direction and magnitude
What quantity is force?
Vector
Give 5 examples of a vector quantity
Force, velocity, displacement, acceleration, momentum
What does a scalar quantity have?
Magnitude and no direction
Give 5 examples of a scalar quantity
Speed, distance, mass, temperature, time
What are vectors usually represented by in diagrams?
Arrows
What do the length and direction of a vector arrow show?
Length shows the magnitude and the direction shows the direction of the quantity
What is gravitational force?
The force of attraction between masses
What is mass?
The amount of matter in an object
What is weight?
The amount of gravitational force acting on an object
What is the difference between mass and weight?
Mass will always stay the same and weight would change in different parts of the universe
What is weight measured in and how?
Newtons with a calibrated spring balance or newtonmeter
What is mass measured in?
Kilograms
How can you calculate weight using mass?
Weight = Mass X Gravitational Field Strength
What happens when a force moves an object through a distance?
Energy is transferred and work is done
What is work done?
The amount of energy transferred to an object by an external force when it is moved over a certain distance by that force
What does it mean if an object is in equilibrium?
The forces acting on it are balanced
What is the phrase used when a spring is stretched so far it cannot return to its original form?
Limit of proportionality
What is extension directly proportional to?
Force
When does extension stop being directly proportional to force?
When the force is too great and the spring reaches its limit of proportionality
What is a moment?
A force can cause an object to rotate, the turning effect of a force is its moment
What is the equation linking moments to force?
Moment = Force x Distance
How do levers make it easier to do work?
They increase the distance from the pivot at which the force is applied and since M=FD, less force is needed to get the same moment
How do gears work?
They transmit rotational effects, their teeth interlock causing a domino effect of turning, the larger gear will turn slower than the smaller gear