In a Michelson experiment for measuring speed of light, the distance travelled by light between two reflections from the rotating mirror is 4.8 km. The rotating mirror has a shape of a regular octagon. At what minimum angular speed of the mirror (other than zero) the image is formed at the position where a nonrotating mirror forms it ?
In a Michelson experiment for measuring speed of light, the distance travelled by light between two reflections from the rotating mirror is 4.8 km. The rotating mirror has a shape of a regular octagon. At what minimum angular speed of the mirror (other than zero) the image is formed at the position where a nonrotating mirror forms it ?
Text Solution
Verified by Experts
The correct Answer is:
A, C
In the given Michelson experiment
`D=4.8km=4.8xx10^3m`
We know `c=D(omegan)/(2pi)`
`rarr w=(2pic)/(DN) rad/sec`
`=c/(DN) rev/sec` ltbr. `=(3xx10^8)/((4.8xx10^3xx8)`
`=(7.8)xx10^3 rev/sec`
`D=4.8km=4.8xx10^3m`
We know `c=D(omegan)/(2pi)`
`rarr w=(2pic)/(DN) rad/sec`
`=c/(DN) rev/sec` ltbr. `=(3xx10^8)/((4.8xx10^3xx8)`
`=(7.8)xx10^3 rev/sec`
Topper's Solved these Questions
Similar Questions
Explore conceptually related problems
There are two plane mirror with reflecting suface faciing each other.The mirrors are moving with speed v away form each other .A point object is placed between the mirrors.The velocity of the n-th image will be
A bird is flying with a velocity v between two long vertical mirrors making an angle theta with mirror M_(1) as shown. Then what will be the relative velocity of approach between the images formed by the mirrors due to the 1st reflection in each of them
Two plane mirrors makes an angle of 120^(@) with each other. The distance between the two images of a point source formed in them is 20 cm . Determine the distance from the light source of the point where the mirrors touch, the light source lies on the bisector of the angle formed by the mirrors.
Two blocks of mass m_(1)=10kg and m_(2)=5kg connected to each other by a massless inextensible string of length 0.3m are placed along a diameter of the turntable. The coefficient of friction between the table and m_(1) is 0.5 while there is no friction between m_(2) and the table. the table is rotating with an angular velocity of 10rad//s . about a vertical axis passing through its center O . the masses are placed along the diameter of the table on either side of the center O such that the mass m_(1) is at a distance of 0.124m from O . the masses are observed to be at a rest with respect to an observed on the tuntable (g=9.8m//s^(2)) . (a) Calculate the friction on m_(1) (b) What should be the minimum angular speed of the turntable so that the masses will slip from this position? (c ) How should the masses be placed with the string remaining taut so that there is no friction on m_(1) .
A horizontal ray of light passes through a prism of index 1.50 and apex angle 4^(@) and then strikes a vertical mirror , as shown in the figure. Through what angle must the mirror be rotated if after reflection the ray is to be horizontal?
A ray of light travelling with a speed c leaves point 1 shown in figure and is reflected to point 2. The ray strikes the reflecting surface at a distance x from point 1. According to Fermat's principle of least time, among all possible paths between two points , the one actually taken by a ray of light is that for which the time taken is the least (In fact there are some cases in which the time taken by a ray is maximum rather than a minimum). Find the time for the ray to reach from point 1 to point 2.
A plane mirror of circular shape with radius r=20cm is fixed to the ceiling .A bulb is to be placed on the axis of the mirror.A circular area of radius R=1m on the floor is to be illuminated after reflection of light from the mirror. The height of the room is 3m What is maximum distance from the center of the mirror and the bulb so that the required area is illuminated?
A concave mirror of focal length 20 cm is cut into two parts from the middle and the two parts are moved perpendicularly by a distance 1 cm from the previous principal axis AB .find the distance between the images formed by the two parts?
When two plane mirrors subtend an angle theta between them, then a ray of light incident parallel to one of them retraces its path afer n reflections such that ntheta=c (where c is constant) What is the angle of c?
A ray of light travelling with a speed c leaves point 1 shown in figure and is reflected to point 2. The ray strikes the reflecting surface at a distance x from point 1. According to Fermat's principle of least time, among all possible paths between two points , the one actually taken by a ray of light is that for which the time taken is the least (In fact there are some cases in which the time taken by a ray is maximum rather than a minimum). Under what condition is time taken least?