CP1 Flashcards
Define scalar
Quantity with a size (magnitude) only
Give 2 examples of scalar quantities
Mass, speed, energy, time
Define vector
Quantity with a size (magnitude) and a direction
Give 2 examples of vector quantities
Velocity, weight, all forces, acceleration, momentum
Give a pair of quantities where one is a vector and the other a scalar
Speed-velocity; mass-weight
What is meant by the term ‘displacement’
Distance from start to finish in a straight line
What is the equation that links the change in velocity, acceleration and time?
Acceleration = change in velocity / time a = v – u /t
An object accelerates from 10m/s to 20m/s in 5 seconds. Calculate the acceleration
a = 20-10 / 5 a=2m/s2
Acceleration can be linked to initial velocity, final velocity and distance:
v2-u2 = 2 x a x x
Rearrange the equation to calculate distance (x)
x = v2-u2 / 2 x a
What is the acceleration due to gravity?
10 m/s2 (or 9.8m/s2)
What is the equation that links time, speed and distance?
Speed = distance / time
Estimate of speed
Walking
1.5 m/s Cycling
6 m/s
An object travels 10m in 2 seconds. Calculate the speed10/2 = 5m/s
How far would ThrustSSC travel in 5 seconds if the speed was 341m/s?
d = s x t; d = 341 x 5 = 1705m
What does a horizontal line represent on a distance time graph?
Object is stationary
What does a sloping line represent on a velocity-time graph?
Acceleration
What does a horizontal line represent on a velocity-time graph?
Constant speed
How do you calculate the distance travelled on a sloped part of the graph?
area under the graph
