- A8p × 107
- B4p × 106
- C2p × 105
- D$\pi$ × 104
Explanation:
Frequency of wave f = 40 × 106 Hz
Angular frequency, $\omega=2\pi\text{v}$
$\omega=2\pi\times40\times10^6$
$\Rightarrow\omega=8\pi\times10^7\frac{\text{rad}}{\text{s}}$
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A star emits light of 5500 Å wavelength. Its appears blue to an observer on the earth, it means
|
(a) Star is going away from the earth |
(b) Star is stationary |
|
(c) Star is coming towards earth |
(d) None of the above |
Binding energy of a nucleus is
|
(a) Energy given to its nucleus during its formation |
|
(b) Total mass of nucleus converted to energy units |
|
(c) Loss of energy from the nucleus during its formation |
|
(d) Total K.E. and P.E. of the nucleons in the nucleus |
The mass number of a nucleus is
|
(a) Always less than its atomic number |
|
(b) Always more than its atomic number |
|
(c) Always equal to its atomic number |
|
(d) Sometimes more than and sometimes equal to its atomic number |
Two spherical conductors A and B of radius a and b (b > a) are placed in air concentrically B is given charge + Q coulomb and A is grounded. The equivalent capacitance of these is
|
(a) 4π |
(b) 4 π |
(c) 4 π |
(d) 4 π |
$\text{3V}\cos\theta$
$2\text{V}\cos\theta$
$\frac{3}{2}\text{V}\cos\theta$
$\text{V}\cos\theta$
Variation of current and voltage in a conductor has been shown in the diagram below. The resistance of the conductor is
|
(a) 4 ohm |
(b) 2 ohm |
(c) 3 ohm |
(d) 1 ohm |
The size of an object as perceived by an eye depends primarily on: