A) halved
B) doubled
C) zero
D) independent of radius of curvature
Correct Answer: B
Solution :
Formula for speed of light in Foucaults experiment \[c=\frac{8\pi {{a}^{2}}nd}{x(a+b)}\] n = Frequency of rotating mirror a = Radius of curvature of concave mirror b = Distance between rotating mirror and convex lens \[x=\] Image shift According to question, \[a>>b\] So, b is neglected \[\therefore \] \[c=\frac{8\pi {{a}^{2}}nd}{xa}\] \[c=\frac{8\pi a\,n\,d}{x}\] First case, \[x=\frac{8\pi a\,n\,d}{c}\] Second case, \[x=\frac{8\pi (2a)nd}{c}\] \[\therefore \] \[\frac{x}{x}=\frac{2a}{a}\] \[x=2x\] So, the image shift becomes double.You need to login to perform this action.
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