Linear Motion Flashcards
What is mechanics?
The study of the motion of objects
What is displacement?
Distance in a given direction as the crow flies
What is velocity?
The rate of change of displacement with time (Speed in a given direction)
What is average velocity?
Displacement undergone divided by time elapsed
What is constant velocity?
The velocity of an object if it does not speed up, slow down or change direction
What is instantaneous velocity?
How fast the object is going at a given time
What is used (in the lab) to measure velocity?
Ticker timer and tape, scalar timer and light gates
Explain how a ticker timer and tape works.
The ticker timer has a small hammer that strikes 50 times per second. The tape is attached to the moving object and is pulled through.
What are a scaler timer and light gates?
A piece of equipment that has a light source (LED) on one side and a light receptor (photodiode) on the other side. Every time the light beam is broken, the receptor tells the scaler timer. If an object passes through the light gate, the gate will start the scaler timer as it enters and stop the scaler timer as soon as it has gone.
What is acceleration?
The rate of change of velocity with time (change in velocity)
Positive acceleration means…
The object is speeding up
Negative acceleration means…
The object is slowing down
Zero acceleration means…
The object is moving at constant velocity
