Light Intensity - Questions
The Light Intensity Concept Builder is comprised of 36 questions. The questions are divided into 12 different question groups. Questions in the same group are rather similar to one another. The Concept Builder is coded to select at random a question from each group until a student is successful with that group of questions.
There are three different activities that can be engaged in through the Concept Builder. Those three activities are differentiated as follows:
- Power Up: Question Groups 1-3 ... Effect of Light Bulb Power (Watts) on Illuminance
- Distance Matterse: Question Groups 4-8 ... Effect of Bulb-Surface Separation Distance on Illuminance
- Putting it All Together: Question Groups 9-12 ... Effect of Bulb Power and Separation Distance on Illuminance
The questions from each group are shown below. Teachers are encouraged to view the questions in order to judge which activities are most appropriate for their classes. We recommend providing students two or more options.
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Light Intensity
Activity 1: Power Up
Question Group 1
Question 1
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 1800 lux. What would be the illuminance on a surface the same distance away if illuminated by a 120-Watt bulb?
Question 2
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 2400 lux. What would be the illuminance on a surface the same distance away if illuminated by a 120-Watt bulb?
Question 3
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 3600 lux. What would be the illuminance on a surface the same distance away if illuminated by a 120-Watt bulb?
Question Group 2
Question 4
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 1800 lux. What would be the illuminance on a surface the same distance away if illuminated by a 240-Watt bulb?
Question 5
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 2400 lux. What would be the illuminance on a surface the same distance away if illuminated by a 240-Watt bulb?
Question 6
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 3600 lux. What would be the illuminance on a surface the same distance away if illuminated by a 240-Watt bulb?
Question Group 3
Question 7
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 1800 lux. What would be the illuminance on a surface the same distance away if illuminated by a 30-Watt bulb?
Question 8
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 2400 lux. What would be the illuminance on a surface the same distance away if illuminated by a 30-Watt bulb?
Question 9
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 3600 lux. What would be the illuminance on a surface the same distance away if illuminated by a 30-Watt bulb?
Activity 2: Distance Matters
Question Group 4
Question 10
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 1800 lux. What would be the illuminance on a surface 2.0 meters away if illuminated by the same bulb?
Question 11
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 2400 lux. What would be the illuminance on a surface 2.0 meters away if illuminated by the same bulb?
Question 12
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 3600 lux. What would be the illuminance on a surface 2.0 meters away if illuminated by the same bulb?
Question Group 5
Question 13
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 1800 lux. What would be the illuminance on a surface 3.0 meters away if illuminated by the same bulb?
Question 14
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 2400 lux. What would be the illuminance on a surface 3.0 meters away if illuminated by the same bulb?
Question 15
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 3600 lux. What would be the illuminance on a surface 3.0 meters away if illuminated by the same bulb?
Question Group 6
Question 16
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 1800 lux. What would be the illuminance on a surface 4.0 meters away if illuminated by the same bulb?
Question 17
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 2400 lux. What would be the illuminance on a surface 4.0 meters away if illuminated by the same bulb?
Question 18
A light bulb illuminates a surface a distance 1.0 meter away with an illuminance of 3600 lux. What would be the illuminance on a surface 4.0 meters away if illuminated by the same bulb?
Question Group 7
Question 19
A light bulb illuminates a surface a distance 1.00 meter away with an illuminance of 1800 lux. What would be the illuminance on a surface 0.50 meters away if illuminated by the same bulb?
Question 20
A light bulb illuminates a surface a distance 1.00 meter away with an illuminance of 2400 lux. What would be the illuminance on a surface 0.50 meters away if illuminated by the same bulb?
Question 21
A light bulb illuminates a surface a distance 1.00 meter away with an illuminance of 3600 lux. What would be the illuminance on a surface 0.50 meters away if illuminated by the same bulb?
Question Group 8
Question 22
A light bulb illuminates a surface a distance 1.00 meter away with an illuminance of 1800 lux. What would be the illuminance on a surface 0.25 meters away if illuminated by the same bulb?
Question 23
A light bulb illuminates a surface a distance 1.00 meter away with an illuminance of 2400 lux. What would be the illuminance on a surface 0.25 meters away if illuminated by the same bulb?
Question 24
A light bulb illuminates a surface a distance 1.00 meter away with an illuminance of 3600 lux. What would be the illuminance on a surface 0.25 meters away if illuminated by the same bulb?
Activity 3: Putting it All Together
Question Group 9
Question 25
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 1800 lux. What would be the illuminance on a surface a distance 2•d away (i.e., twice as far away) when illuminated by a 120-Watt bulb?
Question 26
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 2400 lux. What would be the illuminance on a surface a distance 2•d away (i.e., twice as far away) when illuminated by a 120-Watt bulb?
Question 27
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 3600 lux. What would be the illuminance on a surface a distance 2•d away (i.e., twice as far away) when illuminated by a 120-Watt bulb?
Question Group 10
Question 28
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 1800 lux. What would be the illuminance on a surface a distance 2•d away (i.e., twice as far away) when illuminated by a 30-Watt bulb?
Question 29
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 2400 lux. What would be the illuminance on a surface a distance 2•d away (i.e., twice as far away) when illuminated by a 30-Watt bulb?
Question 30
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 3600 lux. What would be the illuminance on a surface a distance 2•d away (i.e., twice as far away) when illuminated by a 30-Watt bulb?
Question Group 11
Question 31
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 1800 lux. What would be the illuminance on a surface a distance 0.5•d away (i.e., one-half the distance away) when illuminated by a 120-Watt bulb?
Question 32
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 2400 lux. What would be the illuminance on a surface a distance 0.5•d away (i.e., one-half the distance away) when illuminated by a 120-Watt bulb?
Question 33
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 3600 lux. What would be the illuminance on a surface a distance 0.5•d away (i.e., one-half the distance away) when illuminated by a 120-Watt bulb?
Question Group 12
Question 34
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 1800 lux. What would be the illuminance on a surface a distance 0.5•d away (i.e., one-half the distance away) when illuminated by a 30-Watt bulb?
Question 35
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 2400 lux. What would be the illuminance on a surface a distance 0.5•d away (i.e., one-half the distance away) when illuminated by a 30-Watt bulb?
Question 36
A 60-Watt bulb illuminates a surface a distance d away with an illuminance of 3600 lux. What would be the illuminance on a surface a distance 0.5•d away (i.e., one-half the distance away) when illuminated by a 30-Watt bulb?