In an experiment to measure the speed of light by Fizeau's apparatus, following data are used :
Distance between the mirrors = 12.0 km,
Number of teeth in the wheel = 180.
Find the minimum angular speed of the wheel for which the image is not seen.
In an experiment to measure the speed of light by Fizeau's apparatus, following data are used :
Distance between the mirrors = 12.0 km,
Number of teeth in the wheel = 180.
Find the minimum angular speed of the wheel for which the image is not seen.
Distance between the mirrors = 12.0 km,
Number of teeth in the wheel = 180.
Find the minimum angular speed of the wheel for which the image is not seen.
Text Solution
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The correct Answer is:
A, B, D
In the given Fizeau's apparatus
`D=12 km=12xx10^-3m`
n=180
`c=3xx10^8m/sec`
We know c=(2Dnomega)/pi`
`rarr w=(pc)/(2Dm)rad/sec`
`=(pc)/(2Dm)xx180/pdeg/s`
`rarr w=180xx3xx10^8/(24xx10^3)xx180`
`=1.25xx10^4deg/sec`
`D=12 km=12xx10^-3m`
n=180
`c=3xx10^8m/sec`
We know c=(2Dnomega)/pi`
`rarr w=(pc)/(2Dm)rad/sec`
`=(pc)/(2Dm)xx180/pdeg/s`
`rarr w=180xx3xx10^8/(24xx10^3)xx180`
`=1.25xx10^4deg/sec`
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