s3 phy Flashcards
define a physical quantity
a physical quantity is a quantity that can be measured. It consists of a numerical magnitude and a unit.
how long is a period of a pendulum
the time taken for one complete oscillation
how long is one complete oscillation
each complete to-and-fro motion
what is a scalar quantity
physical quantities that only have magnitude
what is a vector quantity
physical quantities that have both magnitude and direction
name 5 examples of scalar quantities
distance, speed, mass, energy, time
name 5 examples of vector quantities
displacement, velocity, acceleration, force, weight
define speed
speed is the distance moved per unit time
speed formula
distance/time
define velocity
velocity is the rate of change of displacement
formula of velocity
displacement/time taken
how do we calculate average speed?
total dist travelled/total time taken
how do we calculate the average velocity
total displacement/total time taken
define acceleration
acceleration is the rate of change of velocity
how do we calculate acceleration
change of velocity/time taken
define uniform acceleration
the constant rate of change of velocity
how can we calculate uniform acceleration
change in velocity/change in time
what does the gradient of a distance-time graph show
the speed of an object
what does the gradient of a speed-time graph show
the acceleration of the object
how can you calculate the distance of an object
the area under the speed-time graph
define mass
mass is a measure of the amount of matter in a body
define weight
the gravitational force acting on an object that has mass
what is a gravitational field
a gravitational field is a region in which a mass experiences a force due to gravitational attraction
define gravitational field strength
the gravitational force per unit mass placed at that point
how do we calculate gravitational field strength
g = weight/mass of the object
if an object were to free fall under gravity without air resistance, we ca find its acceleration using the equation
F(resultant force) = mass times acceleration
define density
mass per unit volume
calculate density
p(density) = mass/volume