Investigating Motion Flashcards
Describe how you would set up equipment for an investigation into the effect of changing the mass of a trolley on its acceleration.
- Get a flat ramp for trolley to move down
- Set up two light gates at the side of the ramp, connected to a data logger to measure speeds
- Position a pulley at the end of the ramp
- Place card onto trolley so it can be detected by the light gates
- Run string attached to the trolley through the pulley at end of ramp
- Hook hanging mass onto end of string
What measurements should be taken when investigating motion?
- Mass of trolley
- Mass of hanging hook
- Length of piece of card which will interrupt light gate beams
- Initial speed of trolley
- Final speed of trolley
- Time taken for trolley to travel through two light gates
Give one benefit of using light gates to take measurements.
Any from:
- Light gates remove human error caused by reaction times
- A light gate can be directly linked to a data logger
(Exam-style question)
Describe how a student could use their measurements to determine the acceleration of the trolley.
Calculate the difference in the trolley’s speed between two light gates, then divide this by time taken to travel between gates
Predict how the acceleration of the trolley will change as the mass of the trolley is increased.
As the mass of the trolley is increased, the acceleration decreases
A student wants to calculate the uncertainty of one of their mean results.
Describe how they can do this.
Find the range of the results used to calculate the mean, then use uncertainty = range ÷ 2
(Exam-style question)
The student could add mass to the weight hanger
(Exam-style question)
The mass can be kept constant by transferring it between the trolley and hanger when needed
(Exam-style question)
The student could raise one end of the runway so that gravity on the trolley balances the force of friction
