Required Practicals Paper 2

Question 1

RP 6: Stretching a spring

Answer 1

Attach a pointer to the base of the spring, ensuring it’s parallel to the workbench and perpendicular to metre ruler.
Align the top of the ruler with the top of the spring
Measure the initial length of the spring without any weights attached
Add a 1N weight to the base of the spring and record the length of the spring
Repeat and continue to add weights
Calculate the extension of the spring for each weight by subtracting the initial length of the spring from each different length of the spring.
Plot the graph of force against extension. Calculate the gradient

Question 2

RP 7: Acceleration

Answer 2

Method:
1. Draw a series of straight lines, each 20 cm apart, perpendicular to the edge of the bench.
2. Attach the car to the string at one end, with the other end running across the bench pulley.
3. Attach the weight stand to the loose end of string (you may need to tie a knot at that end, to hook the stand onto). Hold the weight of the pulley, so it doesn’t pull the car but so that the string is fully extended.
4. Release the weight stand (allowing it to fall) and begin the timer. Stop timing when the car hits the pulley at the other end of the bench.
To Investigate Changing Force on a Constant Mass:
* Add a 10g mass to the weight stack, holding it so it doesn’t pull the car but the string is fully extended.
* Release the weights and time the car travelling across the bench.
* Repeat the experiment by adding 10g weights and recording the time for each.
To Investigate Changing Mass with a Constant Force:
* Attach a 10g mass on top of the toy car, using either the Blu-Tac or rubber bands.
* Pull the car back to the starting chalk line.
* Release the car and time how long it takes for the car to travel across the bench.