VITEEE 2017 :: Physics :: General questions

• Physics - General questions

A vessel of depth 2d cm is half-filled with a liquid of refractive index μ₁, and the upper half with a liquid of refractive index μ₂. The apparent depth of the vessel seen perpendicularly is

Answer:

Explanation:

Apparent Depth = $\frac{d}{\mu_{1}}+\frac{d}{\mu_{2}}$

A conducting circular loop of,radius r carries a constant current i. It is placed in a uniform magnetic field $\bar{B}_{0}$  such that

$\bar{B}_{0}$ is perpendicular to the plane of the loop. The magnetic force acting on the loop is

Answer:

Explanation:

The magnetic field is perpendicular to the plane of the paper. Let us consider two diametrically opposite elements. By Fleming's Left-hand rule on element AB the direction of force will be Leftwards and the magnitude will be

dF= ld/ B sin 90° = Id/B

On element CD, the direction of force will be towards right on the plane of the paper and the magnitude will be dF = Id/B.

A hydrogen atom is in ground state. Then to get six lines in emission spectrurn, wavelength of incident radiation should be

Answer:

Explanation:

Number of possible spectral lines emitted when an electron jumps back to ground state from n^th orbit = $\frac{n(n-1)}{2}$

Here, $\frac{n(n-1)}{2}$ = 6 → n = 4

Wavelength λ from transition from n = 1 to n = 4 given by,

$\frac{1}{\lambda} = R\left(\frac{1}{1}-\frac{1}{4^{2}}\right)$ 

$\Rightarrow\lambda = \frac{16}{15R}= 975 Å$

Six identical conducting rods are joined as shown in figure. Points A and D are maintained at 200°C and 20°C respectively. The temperature of junction B will be

Answer:

Explanation:

The equivalent electrical circuit of the arranganent is shown in figure.

Temperature difference between the end points  A and D =  200 - 20 = 180°C

As the resistances for the three parts are equal, the temperature difference must be distributed equally in the three parts 

(180/ 3=60°C)

.'. Temperature of B = 200°C - 60°C = 140°C

Which of the following does not support the wave nature of light?

Answer:

Explanation:

Photoelectric effect does not support the wave nature of light.

• Physics - General questions