Physics Year 1 Experiments

After experiments for drawing graphs, draw…

• Either re-arrange equation to y=mx+c

• or for y=kx, draw y against x and k is gradient

Always say ‘repeat 3 times for each angle, etc. and take mean’ and repeat experiment overall to find mean overall answer. This ‘REDUCES ERROR’

What variables to mention

• Independent

• Dependent

• Control

Common equipment

• Single/dual interrupt card

• Data logger

• ruler

• balance

• protractor

• light gate

• Stopwatch

How many sig. fig. should absolute uncertainty be to

1 or 2

The 3 methods to measure g for Earth

• Dropping ruler with dual interrupt card through lightgate to measure g directly

• Dropping ruler with single interrupt card through 2 lightgates positioned vertical distance s apart measuring v and u at each light gate and using suvat to find a which is g

• Drop steel ball through vertical height s and time fall with data logger and trap door using suvat again

Why might an obtained value not be same as accepted value

• Delays in timing equipment

• Resistive forces

• Errors in measurements

An assumption about friction that can be made for experiments

Is constant or is negligible

Why might it be advantageous to plot data points as you are doing experiments

To identify anomalous points quickly and replace by taking another recording

Measurement on Young’s Modulus

• Need wire, tape pointer, metre rules, clamp, pulley wheel, load F

• Measure diameter of wire using micrometer - take 3 readings and find mean

• Calculate A

• Find length of wire and extension for different loads using ruler

• Gradient of straight section of stress strain graph gives E