how to measure speed

-use a meter ruler to measure the distance and use a stopwatch to measure the time taken for an object to move through that distance.

-connect a light gate to a data logger and computer. The computer measures the time taken for the interrupt card to pass through the light gate. Speed = length of card/ time taken.

-send pulses of ultrasound so it reflects off the moving object and measure the time taken for the echo to return. This gives the distance to the object of each pulse. Speed = change in distance between each pulses/ time between pulses