| Light Up My Life: Activity Page 2 | |
 c) Record at least three light sources that humans used to overcome darkness before the invention of electric lights.d) Next, indicate the chronological order in which you think humans used the light sources named in Step (c) from earliest (1) to most recent. 2. Try reading with a candle as the only source of light. Use a light sensor to determine the illuminance at measured distances from a candle flame. For the first reading, place the light sensor as close to the flame as you can without allowing the flame to heat or damage the sensor. This will give you the highest reading of illuminance that is safe for the equipment. (Illuminance is the amount of light that arrives at each unit of surface area from a light source. You will express illuminance in footcandles (fc). This is the unit used almost exclusively in the United States lighting industry.) a) Make a table, similar to the following, to record your results. Record the illuminance and the distance between the sensor and the flame. |
Always wear approved eye protection in a laboratory. Secure any loose clothing and tie back longer hair when working with open flames. Never leave a burning candle unattended. |
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Do not allow the flame to heat the sensor. Keep it far enough from the flame to prevent damage to the sensor. |