Paper 2 practicals Flashcards
required practical: acceleration and forces
Trolley method
1) Cut an interrupt card to a known length (such as 10 cm) and attach it to a trolley
2) Set up the equipment: 2 light gates, a trolley with a piece of card. attach a string to the trolley. then attach the string to a hook with masses and loop it around a pulley.
3) Make sure that the card will pass through both gates before the masses strike the floor (or else it would stop accelerating)
4) Set the data logging software and input the length of the card to calculate acceleration.
5) Use scales to measure the total mass of the hook, string and weight stack. Record this value.
6) Attach the full weight stack (6 x 10g masses) to the end of the string.
7) mark a starting line on the table so that the trolley always travels the same distance to the light gate
8) place the trolley on the starting line and release
repeat to get an average
What does the light gates and the data logger do?
light gates and data logger measure the acceleration
when the trolley passes through them it sends signals to the data logger, which takes the velocity readings
required practical: acceleration and forces
Glider method
1) Position an air track on a bench with a bench pulley at one end and two light gates above the track. Cut an interrupt card to a known length (such as 10 cm) and attach it to an air track glider.
2) Connect the glider to a hanging mass by a string the length of the air track passing over the bench pulley.
3) Make sure the air track is level and that the card will pass through both gates before the mass strikes the floor.
4) Set the data logging software to calculate acceleration.
5) Add 5 × 20 g slotted masses (0.98 N of force) to the end of the string.
6) Release the glider, then record the weight and acceleration.
Repeat steps 4 and 5 two more times, and calculate a mean value for the acceleration.
How do you investigate the effect of MASS for the acceleration required practical?
Add masses to the trolley/ glider one at a time to increase the mass of the system.
Don’t add masses to the hook, or you’ll change the force.
Record the average acceleration for each mass
How do you investigate the effect of FORCE for the acceleration required practical?
Trolley :
you need to keep the total mass of the system the same, but change the mass on the hook :
start with all of the masses loaded onto the trolley and transfer the masses to the hook one at a time, to increase the accelerating fore.
record the average acceleration for each force
Glider:
Repeat steps 4 to 6, removing one of the slotted masses each time and place on glider to keep the total mass of the system the same
