(1.6 - 1.10) Acceleration + Velocity

What is velocity?

Speed in a certain direction.

What is acceleration?

The rate of change of velocity per unit of time.

What is the equation linking acceleration, time and velocity + units?

acceleration = change in velocity / time taken

a = (v-u) / t (v= final , u= initial)

m/s² = (m/s) / s

What is the graph linking velocity, time and acceleration? Name the parts.

A velocity time graph in which the x axis shows time and the y axis shows velocity. The gradient represents the acceleration.

What does the area between the line and the x axis represent?

The distance travelled.

On a velocity time graph, what does it mean if the line is flat? Why?

The object is moving at a constant speed. The gradient is acceleration- no gradient = no change in speed.

Describe a ticker timer experiment to measure velocity.

A ticker timer makes dots on the tape every 50th of second.

The faster the tape is pulled, the further the dots are.

Ensure you count the spaces and not the dots.

Measure the length of tape and divide it by how long it took to go through the ticker timer (each space = 1/50 s).

v = d / t so the velocity can be calculated.

Describe a light gate experiment to measure velocity.

A light gate has an air track to eliminate as much friction as possible.

It consists of an infrared transmitter and a receiver between the gates.

When the signal is obstructed by an object, the time interval between the gates is recorded.

Then, the equation v = s / t can be used to calculate the velocity- assuming there is no acceleration.

What is the relationship between final speed, initial speed, acceleration and distance.

final speed² =

initial speed² + 2*acceleration*distance)