The sun emits a light with maximum wavelength 510 mm while another star X emits a light with maximum wavelength of 350 nm. What is the ratio of surface temperature of sun and the star X
|
(a) 2.1 |
(b) 0.68 |
(c) 0.46 |
(d) 1.45 |
(b) 0.68
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
In a spherical condenser radius of the outer sphere is R. The different in the radii of outer and inner sphere in x. Its capacity is proportional to
|
(a) |
(b) |
(c) |
(d) |
Assertion : The temperature coefficient of resistance is positive for metals and negative for P-type semiconductor.
Reason : The effective charge carriers in metals are negatively charged whereas in P-type semiconductor they are positively charged.
|
(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
|
(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
|
(c) If assertion is true but reason is false. |
|
(d) If the assertion and reason both are false. |
Electric field strength due to a point charge of 5μC at a distance of 80 cm from the charge is
|
(a) |
(b) 7 |
(c) 5 |
(d) 4 |
In photoelectric effect if the intensity of light is doubled then maximum kinetic energy of photoelectrons will become
|
(a) Double |
(b) Half |
(c) Four time |
(d) No change |
