Practicals

• Stationary waves on a string (determining wave speed)

  IV: length DV: frequency

  Clamp stand and attach string to a vibration and signal generator at one end

  At other end Attach to a mass using a pulley

  Measure length using a ruler from the generator to the bridge

  Measure frequency using signal generator

  Calculate time period t=1/f

  Plot a length-time graph v=2L/t

  Gradient = 1/2 v

  
• Measuring the wavelength of light with a double slit 


  IV: distance between slits and screen (d)

  DV: fringe separation (x)

  Use a class 2 laser

  Place slits 1 metre from screen

  Use white paper as the screen to avoid reflection

  Measure the distance from screen using a ruler

  Measure fringe separation by measuring the distance of 10 gaps and then divide by 10

  Plot a x-d graph

  Wavelength =ax/d

  So wavelength = Gradient/ slit separation

  Slit separation should be stated on the slits
• Measuring wavelength of light with a diffraction grating


  use class 2 laser

  Place diffraction grating 1 metre away from white screen

  Turn laser on

  Measure distance between the maxima

  Find the angle using tan= distance between maxima /d

  Wavelength = dsin/n

  Repeat for all values of n and find the mean
• Measuring resistivity along a wire

  Attach wire in a circuit, ammeter in series and voltmeter in parallel

  Measure diameter of wire 3 times using a micrometer a find a mean

  Measure length using ruler

  Vary the length

  Calculate resistance using R=V/I keep current constant

  Plot Resistance-length graph

  P=RA/L

  Gradient x area =resistivity
• Measuring internal resistance

  Set up circuit as shown

  Measure the potential difference using a voltmeter

  Measure current using an ammeter

  Plot a voltage against current graph

  V= emf-Ir

  Gradient=-r

  Y intercept =emf