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A laser produces a beam of light.  All light travels in air at a constant speed of approximately 300 million meters per second. Therefore, a distance can be measured accurately by calculating the time it takes for a laser beam to travel between two points, such as A and B. The beam is timed with precise electronic equipment, calculating and accurately displaying the correct distance.

Laser

The equation used to calculate the distance is:

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Distance (in meters)

= Time (seconds) (Speed of Light in Air(meters/second)

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You are interested in experimenting to find out the time in seconds that it takes for the laser beam to travel over a measured distance of 3000 meters. Solve for this problem.

Time (in seconds) = Distance (in seconds) / Speed of Light in the Air (m/sec)

Time = 3000 / 300,000,000

Time = 0.00001 seconds

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The time for the laser beam to travel from Point A to Point B is 0.003 seconds. What is the distance between the two points ?

Estimate the answer:

ans_a.gif (231 bytes) Less than 100,000  meters
ans_b.gif (220 bytes) Between 100,000 and 500,000 meters
ans_c.gif (227 bytes) Over 500,000 meters

 

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