Remains the same
Collapses
Collapses and diverges again
Diverges
Correct answer is B
No explanation has been provided for this answer.
When a telescope is in normal use, the final image is at
Infinity
The focus
The radius of curvature
The near point
Correct answer is A
No explanation has been provided for this answer.
In a compound microscope, the objective and the eye piece focal lengths are
At infinity
Long
Short
The same
Correct answer is C
No explanation has been provided for this answer.
The focal length of a concave mirror is 2.0cm. If an object is placed 8.0cm from it, the image is at
2.7m
2.0m
2.3m
2.5m
Correct answer is A
\(\frac{1}{U} + \frac{1}{V} = \frac{1}{f}\)
\(\frac{1}{8} + \frac{1}{V} = \frac{1}{2}\)
\(V = \frac{8}{3}\)
\(V = 2.7cm\)
An object is placed 10m from a pinhole camera of length 25cm. Calculate the linear magnification.
2.5x102
2.5x10-2
2.5x10-1
2.5x101
Correct answer is B
\(\text{Linear Magnification} = \frac{\text{Length of Camera}}{\text{Distance of the Object}}\)
\(\text{Linear Magnification} = \frac{25}{1000}\)
\(\text{Linear Magnification} = 2.5 \times 10^{-2}\)