Required Practical: Stationary Waves On A String

Question 1

Describe an investigation into how the frequency of the first harmonic on a piece of string varies with tension/length/m

Answer 1

1) draw apparatus being used
2) adjust length so that is it 1m, measured using a meter ruler
3) increase the frequency using a signal generator until string oscillates at first harmonic. Record this frequency
4) reduce l by 0.1m and adjust f so that string oscillates at first harmonic again. Record this frequency
5) repeat this until l = 0.5m
6) repeat experiment twice more and record mean f for each value of l
7) measure the mass of the string using a balance
8) plot of graph of mean f against 1/l and draw a line of best fit
9) the wave speed will be 2 x gradient

Question 3

How could you change the tension

Answer 3

Repeat experiment with different masses

Question 4

How could you change the mass per unit length

Answer 4

Use different thicknesses of string

Question 5

How can you reduce error in signal generator

Answer 5

Leave for 20 mins and use oscilloscope to verify readings