Light Experiment Apparatus

Question 1

Light meter or photometer (No power supply unit required)

Answer 1

Measures the intensity of viable light directly.

Question 2

LDR + milliammeter + voltmeter + power supply unit,

Or

LDR connected to ohmmeter (No power supply unit required)

Answer 2

LDR can be used to measure the intensity of visible light.

*Always state that when the light intensity increases, the resistance of the LDR decreases

and that the resistance of the LDR is first calibrated against light intensity in a preliminary experiment.

Question 3

Spectrometer

Answer 3

Used to measure small angular deviation of a light beam accurately.

State that this is possible because of its vernier scale

Question 4

Diffraction grating

Answer 4

Used with the spectrometer to measure the wavelength of a source of light.

Question 5

Ray box/light box with slit

Answer 5

A light source which can produce a day of light. Often used together with a rectangular glass block in refractive index expts.

A colour filter may be placed in front of the ray box to allow only a particular frequency of light to pass through.

Question 6

Diode laser

Answer 6

Source of monochromatic laser light.

Question 7

Dark room or sheets of matt black paper rolled into cylindrical tube

Answer 7

Often required to keep out ambient light (light from external environment.