• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Physics Lab Report. Aim: To find out how a light dependent resistor is affected by light intensity.

Extracts from this document...


What is the relationship between light intensity and resistance in a Light Dependent Resistor?

Aim: To find out how a light dependent resistor is affected by light intensity.

Hypothesis: A light dependent resistor is one that changes its resistance with a change in the light intensity on it. Hence if we can find the light intensity that is on the resistor and its resistance, we can see what factor the resistance is affected by.


Independent: Light Intensity

Dependent: Current

Controlled: Voltage, Resistor used, Ambient light, Filament Light Bulb used, light sensor and resistor.


1. Filament Light Bulb

2. Clamp Stand

3. Light Dependent Resistor

4. Voltmeter

5. Wires

6. Light Sensor

7. Logger Pro

8. Laptop

9. Power Supply


1. Connect up all the wires in order to the resistor and the power supply.

...read more.














Data Processing:

First we calculate the average current and average light intesity

Average Light Intensity (Lux)

Average Current (± 0.001A)













Using V=IR we can calculate resistance since voltage was set at 1.2V at the beginning of the trials. We get the following values:

Average Light Intensity

Resistance (ohms)













...read more.


  1. The light sensor gave a band of values in which the intensity could be. It did not give one specific value.
  2. The resistance voltage was given only to one decimal place.

The assumptions in the experiment were:

  1. The light in the room did not change in intensity.
  2. The light sensor and the resistor were the same distance away from the filament bulb.
  3. There was no resistance in the wires.

The improvements that could have been made were:

  1. A better light sensor could have been used.
  2. We could have made sure that the light sensor was exactly the same distance away from the bulb as the resistance.
  3. The room could have been made darker
  4. The experiment could have been carried out further away from other students to prevent the light from their experiment interfering with mine.

...read more.

This student written piece of work is one of many that can be found in our International Baccalaureate Physics section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Physics essays

  1. Testing ohms law on a light bulb and a resistor connected to a source ...

    This in turn shows that the voltage and the current are not proportional. Also seeing from table 1.1 the light bulb does not have constant resistance. So the light bulb does not obey ohm's law. This is because a light bulb is a non ohmic conductor.

  2. IB Specific Heat Capacity Lab

    Initial temperature of Solid (Bob) (?B) Temperature of Water Bath (T3) Therefore, change in the total heat gained by water and calorimeter is directly proportional to change in the initial temperature of Solid which is directly proportional to the temperature of Water Bath: ?Hs????B???T3 DATA SYMBOLS UNCERTAINITIES TRIAL 1 TRIAL 2 TRIAL 3 1 Temperature of Water Bath ( oC )

  1. To test the ohmic and non-ohmic behavior in a resistor and a bulb

    Two wires were connected from resistor to voltmeter in parallel. One to (V) outlet and another to (com) outlet. 5. The power supply was then turned on and the current in the ammeter was read at different voltage values which were set by adjusting the knob on the power supply equipment.

  2. The Refraction of Light Lab

    Evaluation: The method used in this experiment was indeed very successful and had very few flaws. The only real main weakness of the method was that the angles and scales used were so small that it was at times very hard to be any more accurate than to a whole degree.

  1. Simple Harmonic Motion Physics HL Lab Report

    T/s � ?T = � 0.5 s Length L/cm � ?L = � 0.3cm 29.7 3.0 50 cm 25.7 2.6 40 cm 22 2.2 30 cm 19.5 2 20 cm 14 1.4 10 cm Now plotting a graph of Length (L)

  2. How does the sinkage depth of a tyre affect its rolling resistance ?

    The absolute uncertainties that were obtained in our experiment for the rolling resistance were low , this shows that the values that we have obtained are precise . Performing this experiment at a small scale makes the rolling resistance negliblie.

  1. HL Physics Revision Notes

    Ek=.5mv2=.5mw2(A2-x2) Ep=.5mw2x2 Total energy, Et=Ek+Ep=1/2mw2A2 4.3 Forced Oscillations and Resonance: Damping involves a frictional/dissipative force that is always in the opposite direction to the direction of motion of the oscillating particle. As the particle oscillates it does work against this force and loses energy Underdamping: The resistive force is so small that a small fraction of energy is removed every cycle.

  2. Light Intensity Investigation

    To determine the LUX illuminated at various distances, we will use Data Studio to give us accurate measurements of light hitting the light sensor that will be located at one of the ten distances, thus giving us our measurement for the particular trial.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work