A leaf which contains only green pigments is illuminated by a laser light of wavelength 0.6328 μm. It would appear to
Options
(a) black (b) green (c) brown (d) red
Correct Answer:
black
In Young’s double slit experiment, when wavelength used is 6000Å and the screen is 40 cm from the slits, the fringes are 0.012 cm wide. What is the distance between the slits?
Options
A common emitter amplifier is designed with n-p-n transistor (α=0.99). The input impedence is 1kΩ and load is 10kΩ. The voltage gain will be
Options
(a) 9900 (b) 99 (c) 9.9 (d) 990
Correct […]
In a laser tube, all the photons
Options
(a) have same energy (b) have same wavelength (c) move in same direction (d) move with same speed
Correct Answer:
move with same speed
Explanation: […]
In case of linearly polarised light, the magnitude of the electric field vector
Options
(a) does not change with time (b) varies periodically with time (c) is parallel to the direction of propagation […]
Two particles A and B having equal charges +6C, after being accelerated through the same potential difference, enter in a region of uniform magnetic field and describe circular paths of radii 2 cm and 3 […]
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