A uniform disc is acted by two equal forces of magnitude R. One of them, acts tangentially to the disc, while other one is acting a the central point of the disc. The friction between disc surface and ground surface is nF. If r be the radius of the disc, then the value of n would be (in N)
1. 0
2. 1.2
3. 2.0
4. 3.2
While keeping area of cross-section of a solenoid same, the number of turns and length of solenoid one both doubled. The self inductance of the coil will be
1. halved
2. doubled
3. times the original value
4. unaffected
Consider the circular loop having current I and with central point O. The magnetic field at the central point O is
1. acting downward
2. acting downward
3. acting downward
4. acting downward
The Boolean expression , where P and Q are the inputs of the logic circuit, represents
1. AND gate
2. NAND gate
3. NOT gate
4. OR gate
Consider the diagram shown below.
A voltmeter of resistance 150 Ωis connected across A and B. The potential drop across B and C measured by voltmeter is
1. 33 V
2. 26 V
3. 31 V
4. 28 V
Two spherical nuclei have mass numbers 216 and 64 with their radii R1 and R2 respectively. The ratio, \(R_1 \over R_2\) is equal to
1. 3:2
2. 1:3
3. 1:2
4. 2:3
A massless rod S having length 2l has equal point masses attached of its tow ends as shown in the figure. The rod is rotating about an axis passing through its centre and making angle α with the axis. The magnitude of change of momentum of rod i.e. equals
1.
2.
3.
4.
A semiconductor having electron and hole mobilities respectively.
If its intrinsic carrier density is , then what will be the value of hole concentration P for which the conductivity will be minimum at a given temperature?
1.
2.
3.
4.
In terms of basic units of mass (M), length (L), time (T) and charge (Q), the dimensions of magnetic permeability of vacuum would be
1.
2.
3.
4.
The black body spectrum of an object \(O_1\) is such that its radiant intensity (i.e. intensity per unit wavelength interval) is maximum at a wavelength of \(200~\text{nm}\). Another object \(O_2\) has a radiant intensity maximum at a wavelength of \(600~\text{nm}\). The ratio of power emitted per unit area by the source \(O_1\) to that of the source \(O_2\) is:
1. \(1:81\)
2. \(1:9\)
3. \(9:1\)
4. \(81:1\)