The dimensions of where is the permittivity of free space and E is the electric field, are:
1. [ML2T-2]
2. [ML-1T-2]
3. [ML2T-1]
4. [MLT-1]
In producing chlorine by electrolysis, 100 kW power at 125 V is being consumed.
How much chlorine per minute is liberated:
(Given -ECE of chlorine is 0.367 X 10-6 kgC-1)
1.
2.
3.
4.
A man of \(50\) kg mass is standing in a gravity-free space at a height of \(10\) m above the floor. He throws a stone of \(0.5\) kg mass downwards with a speed of \(2\) ms-1. When the stone reaches the floor, the distance of the man above the floor will be:
1. \(9.9\) m
2. \(10.1\) m
3. \(10\) m
4. \(20\) m
| 1. | \(\frac{1}{Ze} \) | 2. | \(v^2 \) |
| 3. | \(\frac{1}{m} \) | 4. | \(\frac{1}{v^4}\) |
A lens having focal length \(f\) and aperture of diameter \(d\) forms an image of intensity \(I\). An aperture of diameter \(\frac{d}{2}\) in central region of lens is covered by a black paper. The focal length of lens and intensity of the image now will be respectively:
1. \(f\) and \(\frac{I}{4}\)
2. \(\frac{3f}{4}\) and \(\frac{I}{2}\)
3. \(f\) and \(\frac{3I}{4}\)
4. \(\frac{f}{2}\) and \(\frac{I}{2}\)
If \(\Delta U\) and \(\Delta W\) represent the increase in internal energy and work done by the system respectively in a thermodynamical process, which of the following is true?
| 1. | \(\Delta U=-\Delta W\), in an adiabatic process |
| 2. | \(\Delta U=\Delta W\) , in an isothermal process |
| 3. | \(\Delta U=\Delta W\), in an adiabatic process |
| 4. | \(\Delta U=-\Delta W\), in an isothermal process |
The total radiant energy per unit area, normal to the direction of incidence, received at a distance \(R\) from the centre of a star of radius \(r,\) whose outer surface radiates as a black body at a temperature \(T\) K is given by: (Where \(\sigma\) is Stefan’s constant):
| 1. | \(\dfrac{\sigma r^{2}T^{4}}{R^{2}}\) | 2. | \(\dfrac{\sigma r^{2}T^{4}}{4 \pi R^{2}}\) |
| 3. | \(\dfrac{\sigma r^{2}T^{4}}{R^{4}}\) | 4. | \(\dfrac{4\pi\sigma r^{2}T^{4}}{R^{2}}\) |
In the given circuit, the reading of voltmeter V1 and V2 are 300 V each. The reading of the voltmeter V3 and ammeter A are respectively:
1. 150 V, 2.2 A
2. 220 V, 2.2 A
3. 220 V, 2.0 A
4. 100 V, 2.0 A
A \(220\) V input is supplied to a transformer. The output circuit draws a current of \(2.0\) A at \(440\) V. If the efficiency of the transformer is \(80\)%, the current drawn by the primary windings of the transformer is:
1. \(3.6\) A
2. \(2.8\) A
3. \(2.5\) A
4. \(5.0\) A
A source S1 is producing 1015 photons per sec of wavelength 5000 Å. Another source S2 is producing 1.02×1015 photons per second of wavelength 5100 Å. Then, (power of S2)/(power of S1) is equal to:
1. 1.00
2. 1.02
3. 1.04
4. 0.98