How Far Does Light Travel in Nine Hours?

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The discussion focuses on calculating the distance light travels in nine hours using the speed of light, approximately 3.00 x 10^8 m/s. The correct formula for distance is distance = velocity x time, and the time must be converted from hours to seconds, resulting in 32,400 seconds for nine hours. Participants clarify that the calculation should yield 9.72 x 10^12 meters or 9.72 x 10^9 kilometers. There is confusion regarding the formula, with one participant incorrectly stating distance equals velocity divided by time. The conversation emphasizes the importance of unit consistency in physics equations.
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please help me!

use the fact that the speed of light in a vacuum is about 3.00*10^8 m/s to determine how many kilemeters a pulse from a laser beam travels in exactly nine hours. answer in units of km


thanks please help!
 
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Distance = velocity * time

Convert the hours to seconds and then plug those values into this formula. Your will get an answer in meters. Convert that to Km.
 
ok...

ok i solved the problem and i got 9.72 * 10^9 but it turned out to be wrong i converted the hours to seconds and got 32400 and i multiplied it by 3.00*8 and got 9.72810^9 which was converted also to km... and the problem is wrong

when i was taught i was taught distance=velocity/time
 
There are 32400 seconds in 9 hours. 34200s * 3*10^8m/s = 9.72*10^12 m or 9.72*10^9 Km.

Whoever taught you that d=V/t taught you wrong. Look at the units. The units on one side of the equation have to equal the units on the other side of the equation just like the quantities.

Distance is in meters
Time is in seconds
Velocity is in meters/second

Meters(D) = \frac{meters(V) \cdot seconds(t)}{seconds(V)}

The seconds cancel out leaving just meters on both sides of the equation.

d=v/t is absurd. Acceleration is v/t. m/s^2
 
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