Advertisements
Advertisements
Question
A ray of light travels a distance of 12.0 m in a transparent sheet in 60 ns. The refractive index of the sheet is ______.
Options
1.33
1.50
1.65
1.75
Solution
A ray of light travels a distance of 12.0 m in a transparent sheet in 60 ns. The refractive index of the sheet is 1.50.
Explanation:
The refractive index can be calculated as,
`mu = c/v`
Where µ is the refractive index, c is the speed of light in air, `v` is the speed of light in the second medium.
Given: Distance d = 12 m, time t = 60 ns = 60 × 10-9 sec
`v = "distance"/"time"`
`v = (12/60) xx 10^9`
`v = (1/5) xx 10^9` m/s
`mu = (3 xx 10^8)/((1"/"5) xx 10^9)`
`mu = 3 xx 10^8 xx 5 xx 10^-9`
μ = 1.5
APPEARS IN
RELATED QUESTIONS
Consider Galileo's method of measuring the speed of light using two lanterns. To get an accuracy of about 10%, the time taken by the experimenter in closing or opening the shutter should be about one tenth of the time taken by the light in going from one experimenter to the other. Assume that it takes 1/100 second for an experimenter to close or open the shutter. How far should the two experimenters be to get a 10% accuracy? What are the difficulties in having this separation?
In Fizeau method of measuring the speed of light, the toothed wheel is placed in the focal plane of a converging lens. How would the experiment be affected if the wheel is slightly away from the focal plane?
In the original Fizeau method, the light travelled 8.6 km and then returned. What could be the difficulty if this distance is taken as 8.6 m?
Light passes through a closed cylindrical tube containing a gas. If the gas is gradually pumped out, the speed of light inside the tube will
The speeds of red light and yellow light are exactly same
Which of the following methods can be used to measure the speed of light in laboratory?
In an experiment with Foucault's apparatus, the various distances used are as follows:
Distance between the rotating and the fixed mirror = 16 m
Distance between the lens and the rotating mirror = 6 m,
Distance between the source and the lens = 2 m.
When the mirror is rotated at a speed of 356 revolutions per second, the image shifts by 0.7 mm. Calculate the speed of light from these data.
For light incident from air on a slab of refractive index 2, the maximum possible angle of refraction is ______.
An air bubble in glass slab of refractive index 1.5 (near normal incidence) is 5 cm deep when viewed from one surface and 3 cm deep when viewed from the opposite face. The thickness of the slab is,
Describe Fizeau’s method to determine the speed of light.
