The angular momentum of an electron is J. The magnitude of the magnetic moment
The angular momentum of an electron is J. The magnitude of the magnetic moment will be
Options
(a) eJ / m (b) (eJ) / (2m) (c) 2meJ (d) (2m) / (eJ)
Correct Answer: […]
Physics
If rope of lift breaks suddenly, the tension exerted by the surface of the lift
If rope of lift breaks suddenly, the tension exerted by the surface of the lift (a = Acceleration of lift) is
Options
(a) mg (b) m(g+a) (c) zero (d) m(g-a)
Correct Answer:
zero
Explanation: […]
A body revolved around the sun 27 times faster than the earth. What is the ratio
A body revolved around the sun 27 times faster than the earth. What is the ratio of their radii?
Options
(a) 1 / 3 (b) 1 / 9 (c) 1 / 27 (d) […]
A sample of HCl gas is placed in an electric field of 5 x 10⁴ N/C
A sample of HCl gas is placed in an electric field of 5 x 10⁴ N/C. The dipole moment of each HCl molecule is 6 x 10⁻³⁰ Cm. The maximum torque that can act on […]
When npn transistor is used as an amplifier
When npn transistor is used as an amplifier
Options
(a) electrons move from base to collector (b) holes move from emitter to base (c) electrons move from collector to base (d) holes move from […]
The frequencies of X-rays,γ-rays and ultraviolet rays are respectively p,q and r
The frequencies of X-rays,γ-rays and ultraviolet rays are respectively p,q and r, then
Options
(a) p greater than q,q greater than r (b) p less than q,q greater than r (c) p less than […]
The magnetic flux linked with a coil at any instant t is given by ?, find emf
The magnetic flux linked with a coil at any instant t is given by ?= (5t³ – 100t + 300). The e.m.f induced in the coil at t=2 sec is
Options
(a) 40 […]
The shortest wavelength in Lyman series is 91.2 nm. The largest wavelength
The shortest wavelength in Lyman series is 91.2 nm. The largest wavelength of the series is
Options
(a) 121.6 nm (b) 182.4 nm (c) 243.4 nm (d) 364.8 nm
Correct Answer:
121.6 nm
The drift velocity does not depend upon
The drift velocity does not depend upon
Options
(a) cross-section of the wire (b) length of the wire (c) number of free electrons (d) magnitude of current
Correct Answer:
length of the wire
If oxygen has root mean square velocity of C m/s, then root mean square velocity of H
If oxygen has root mean square velocity of C m/s, then root mean square velocity of hydrogen will be
Options
(a) C m/s (b) 1 / C m/s (c) 4C m/s (d) C […]