When a lens of focal length f is cut in to two equal halves perpendicular to principal axis, then the focal length of each part of the lens is ……………… 

A) Tropic of Cancer

Correct option is  C) 2f

Correct option is  B) x/2

Correct option is  A) 20 cm

Correct option is  C) 40 cm

When bar magnet is cut into two equal parts, then magnetic moment of each part becomes half of the original directed from S to N pole. ∴ Magnetic moment of the combination...

 U = -12 f = -10  1/v - 1/u = 1/f 1/v + 1/12 = 1/10 1/v = 1/60  \(-\frac{1}{v^2} \)dv or \(\frac{1}{u^2} \)du du = \(\frac{v^2}{u^2} \)du \( \frac{v}{u} \)= same path △u1 = △u2 = 1mm △u1 = △v2  △v2 = vf - vi  x2 = △v2 + 1mm x2...

B) both are concave

B) y – axis, x – axis