Practicals

Question 1

Name 2 methods of determining g and compare them

Answer 1

1. Manual timing using a ruler and a stop clock
2. Using 1 light gate and a double interrupt card

-Manual timing is the least accurate due to human reaction time which gives a resolution of 0.1s, uncertainty of ruler measurements, and high chance of errors
-Light gate and double interrupt card gives results right away with a resolution of 0.01s from a data logger with no chance of calculation error except the measurements of the interrupt card, also more accurate

Question 2

Describe a method of determining g using an electromagnet

Answer 2

Equipment:
- Electromagnet
- Steel ball
- Trapdoor with sensor
- Metre rule
-Timer circuit

1. Set up equipment
2. Deactivate the electromagnet with the ball attached, this drops the ball and starts the timer. Once the ball lands on the trapdoor, the timer stops.
   -Measure the height the ball was dropped from and note down the time
   -Repeat experiment multiple times at the same height and calculate an average before increasing the height and repeating
   -Draw a graph
   h = 1/2g(t^2) +0
   y = m x +c
   -Produces a straight line
   -Find the gradient to get 1/2g and double the value to get g