Given,
R1 = 10 Ω, C1 = 2µF, R2 = 20 and C2 = 4F
The time constants (in µs) for the circuits I, II, III are respectively.
18, 18/9, 4
4, 8/9, 18
18, 4, 8/9
8/9, 18, 4
When a battery connected across a resistor of 16Ω, the voltage across the resistor is 12 V. When the same battery is connected across itt hen the voltage is 11 V. The internal
resistance of the battery (in ohm) is
In the given circuit, the AC source has ω = 100 rad/s, considering the inductor and capacitor to be ideal,
the current through the circuit is 0.4 A
the current through the circuit is 0.3 A
the voltage across 100 Ω resistor is 10 V
the voltage across 50 Ω resistor is 10 V
Which energy state of triply ionized beryllium Be3+ has the same orbital radius as that of ground state of hydrogen atom ?
n = 8 state
n = 5 state
n = 4 state
n = 2 state
In Bohr's model of hydrogen atom, the electron circulates around the nucleus in a path of radius 5 x 10-11 m at a frequency of 6.8 x 1015 Hz. The value of magnetic field and equivalent magnetic moment will be
15.4 T and 8.9 x 10-24 A-m2
13.4 T and 8.9 x 10-24 A-m2
18.4 T and 9.8 x 10-24 A-m2
13.4 T and 9.8 x 10-24 A-m2
A p-n-p transistor is used in common-emitter mode in an amplifier circuit. A change of 45 µA in the base current brings a change of 3 mA in collector current and 0.05 V in base-emitter voltage. If a load of 7 kΩ is used, then voltage gain of amplifier is
729.25
824.41
236.34
424.27
The radius of curvature of a concave mirror, measured by a spherometer is given by . The value of l and h are 4.0 cm and 0.065 cm respectively, where l is measured by a meter scale and h by a spherometer. The relative error in the measurement of R is
0.06
0.6
0.023
2.3
A.
0.06
Light of wavelength λ , strikes a photoelectric surface and electrons are ejected with an energy E. If E is to be increased to exactly twice its original value, the wavelength changes to λ', where