Ch 17 Motion Flashcards
what is distance measured in
meters (m)
what is speed measured in
meters per second (m/s)
what is time measured in
seconds (s)
what is the equation for speed
speed = distance divided by time
what are scalar quantities
quantities that have a size
what are vector quantities
quantities that have both magnitude and direction
what are two vector quantities that control the motion of objects
displacement
velocity
what is displacement
the distance an object travels in a certain direction
what is velocity
the speed of an object and the direction it is traveling in
what is the equation for velocity
displacement divided by time
what does a distance time graph
a distance time graph shows the distance something travels over the time taken to travel that distance
how do you calculate the slope
slope = change in speed divided by change in time = speed
what is acceleration
when speed changes over time
what is the formula for acceleration
change in speed (m/s) divided by time taken (s)
what are contact forces and non contact forces
contact forces two objects have to be in contact
non contact forces two objects don’t have to be in contact
give two examples of contact forces
friction, tension
give two examples of non contact forces
magnetic force, gravity
what is an interaction pair
forces that happen in a pair e.g. boy jumping off ground
what does a network meter measure
forces
what is a newton meter also known as
a spring balance
what can forces also be measured digitally by
a force meter
what is the si unit for force
the newton (N)
what is equilibrium
the state of balance between opposing forces
what is dynamic equilibrium
when the forces are equal but the object still moves e.g. skydiver falls at steady speed from the sky after opening a parachute
what is friction
a force that opposes motion when two object are placed in contact
what are two examples of drag forces
water and air resistance
what is lubrication
it is used to reduce the friction between to solids e.g. oil and wax
what is a reaction force
the force applied by an object in response to the weight of another object e.g. standing on a table
what is an elastic object and give examples
any object that is able to restore its shape after being stretched or compressed e.g. springs, elastic bands
what is elastic limit
the point where they will not restore their shape
what is density
the ratio of mass to volume
what is the formula for density
mass (kg) divided by volume (m3)
what does archimedes principle state
it states that an object placed in water will feel an up thrust equal to the weight of the water displaced
