i and iii only
i and ii only
ii and iii only
i, ii, and iii only
i only
Correct answer is B
No explanation has been provided for this answer.
A 45o triangular glass prism can be used as a reflector of light because
A refraction never takes place in such a prism
the angle of reflection equals the angle of incidence
the refractive index of glass is less than 1
it is transparent
the critival angle angle for glass is less than 45o
Correct answer is E
No explanation has been provided for this answer.
An object is placed 15cm in front of a concave mirror of radius 40cm. The image formed is
virtual and 60cm behind the mirror
real and 60cm behind the mirror
virtual and at infinity
real and at infinity
virtual and 40cm from the mirror
Correct answer is A
u = f
50cm
70cm
100cm
150cm
200cm
Correct answer is A
\(\lambda\) = \(\frac{v}{f}\)
= \(\frac{340}{170}\)
= 2m ; for closed pipe
L = \(\frac{1}{4}\)\(\lambda\)
= \(\frac{1}{4}\) x \(\frac{2}{1}\)
= 0.5m
= 50cm
When a sound wave passes from air into water its
speed and frequency increases but its wavelength remains the same
speed and wavelength increases but its frequency remains the same
speed decreases
speed remains the same but its frequency and wavelength change
speed increases but its frequency and wavelength decreases
Correct answer is C
No explanation has been provided for this answer.