P5-forces Flashcards
What are vector quantities
Have magnitude and direction
What are scalar quantities
Only have magnitude
What are physical quantities that are vector quantities
Force
Velocity
Displacement acceleration
Momentum
What are physical quantities that are scalar quantities
Speed
Distance
Mass
Temperature
Time
What is a contact force
When two objects have to be touching for a force to act, that force is called a contact force
What is a non-contact force
If the object do not need to be touching for the force to act
Mass and weight are directly proportional, how do you calculate the weight
Mass X gravitational field strength
What happens if a force moves an object
When a force moves an object through a distance, energy is transferred and work is done on the object
How would you know if an object is in equilibrium
Forces are balanced
What are the there things that happen if a force is applied to an object
May cause it to stretch, compress or bend
What is elastic deformation
An object has been elastically deformed, if it can go back to its original shape or length after the force has been removed
What is inelastic deformation
An object has been inelastically deformed if it doesn’t return to its original shape or length after the force has been removed
Extension is directionally proportional to force, what is equation for force
Spring constant x extension
What is the difference between scalar and vector
Distance is scalar
Displacement is vector
What is difference between speed and velocity
Speed is how fast you are going with no regard to the direction
Velocity is speed in a given direction
What does friction do
Slows things down
What is Newton’s first law
A resultant force is needed to make something start moving, speed up or slow down
Acceleration is directionally proportional to the resultant force, what is equation for resultant force
Mass x acceleration
What is inertia
Tendency for motion to remain unchanged
What is Newton’s third law
When tow objects interact, the forces they exert in each other are equal and opposite
How do you work out the stopping distance
Thinking distance + braking distance
What is thinking distance affects by
Speed
Reaction time
What is braking distance affected by
Speed
Weather/road surface
Condition of tyres
How good brakes are
What test is used to measure reaction time
Ruler drop test
