# P2.1 - Motion Flashcards

State different ways to measure time (and cons)

\+ use a stopwatch \+ use a light gate cons? there is a reaction time that affects the accuracy and precision is expensive to buy

What is the equation for calculating average speed?

total distance (m) average speed (m/s) = ———————— total time (s)

How many meters are there in one mile?

1609m

What is the difference between a scalar and a vector measurement?

Vector has a magnitude (size) and direction -> represented as an arrow ie. force

Scalar has only magnitude (size) but no direction.

ie. time on a stopwatch (10s)

What is displacement and is it a vector or scalar?

+ The distance from the place you travel

+ is a vector (has direction)

What is speed?

+ a scalar quantity (has no direction)

+ is a measurement

ie. 15m/s

What is velocity?

+ A vector quantity

+ has a direction as well as a magnitude

ie. 15m/s south

+ is in a certain direction

What is the change in velocity per second called?

acceleration

what is the equation for acceleration?

change in velocity (m/s)

acceleration (m/s^-2) = ——————————

time (s)

What is the term when a vehicle slows down (acceleration)?

deceleration

What does a (diagonal) straight line mean on a distance time graph?

the object’s speed is constant because the gradient doesn’t change

What does a horizontal line mean on a distance time graph?

the object is not moving

What does a steep line mean on a distance time graph?

The steeper the line, the faster the object is travelling

How do you calculate speed from a distance time graph?

1) Draw a right-angled triangle underneath the line

2) Find the change in distance and the change in time

3) Use the equation of speed to find out the answer

What is the difference between a distance-time graph and a displacement-time graph?

+ a distance-time graph is scalar

+ a displacement-time graph’s gradient has a velocity

what is the equation for velocity?

change in displacement

velocity = ——————————

time