Topic : introduction

Which of the following systems may be adequately described by classical physics?

A sound source produce sound of intensity $I_0$ at a point. When its amplitude become double and the frequency becomes one fourth then the intensity of sound at same point will be

The current amplification factor for common emitter amplifier is 59. If emitter current is 5 mA . What is value of collector current?

An AND gate can be prepared by repetitive use of

A transistor is used in common-emitter mode in an amplifier circuit. When a signal of 20 mV is added to the base-emitter voltage, the base current changes by 20 $\mu$A and collector current changes by 2 mA. The load resistance is 5 k$\Omega$. The transconductance of the amplifier and voltage gain is respectively

Two liquids of same volume but of different densities, $\rho_1$ and $\rho_2$ are mixed together, then the density of the mixture is

Loading of sucrose in sieve tube elements is

Two amplifiers are connected one after other in series. The first amplifier has voltage gain of 15 and second has voltage gain of 20. If input signal voltage is 0.3 V, the output signal voltage is

Choose the correct statement among the following

A train moves towards a stationary observer with speed 20 m/s. The train sounds a whistle and its frequency is registered by observer as f₁. If the train's speed is increased by 10 m/s, the frequency registered is f₂. If the speed of sound is 300 m/s then f₁ : f₂ will be

The maximum error in measurement of mass and density of a cube are 2% and 1%, respectively. The maximum percentage error in measurement of volume will be

Select the incorrect statement regarding the design of a transistor.

At a place true magnetic dip is 60°. The apparent dip when plane of dip circle is placed at angle of 60° with the magnetic meridian is

In a transistor the current amplification factor α is 0.9. The transistor is connected in common base configuration. The change in collector current when base current changes by 4 mA is

Consider the diameter of a spherical object being measured with the help of a Vernier callipers. Suppose its 10 Vernier Scale Divisions (V.S.D.) are equal to its 9 Main Scale Divisions (M.S.D.). The least division in the M.S. is 0.1 cm and the zero of V.S. is at x = 0.1 cm when the jaws of Vernier callipers are closed. If the main scale reading for the diameter is M = 5 cm and the number of coinciding vernier division is 8, the measured diameter after zero error correction, is:

A physical quantity P is related to four observations a, b, c and d as follows: $P=a^3b^2 / c\sqrt{d}$ The percentage errors of measurement in a, b, c and d are 1%, 3%, 2%, and 4% respectively. The percentage error in the quantity P is

Earth's magnetic field always has horizontal component except at

In a common emitter amplifier the output signal is received across

The threshold intensity of sound is 10⁻¹² W/m². What is the intensity level of sound whose intensity is 10⁻¹⁰ W/m²?

If radius of the sphere is (5.0 ± 0.2) cm, then the percentage error in its surface area is

The heat generated in a circuit is dependent upon the resistance, current and time for which the current is flown. If the errors in measuring the above are 2%, 1% & 3% respectively, then the maximum error in measuring heat will be

At a place, the dip angle is 30° when dip circle is in geographical meridian and the dip angle is found to be 45° when the dip circle is in a plane perpendicular to the geographical meridian. The dip angle in magnetic meridian is

The output of an AND gate is connected to both the inputs of NOR gate. The combination will act as

Radiowave of constant amplitude can be produced with

In a common base amplifier the phase difference between the input and output voltage is

Incorrect statement about silicones is

Which among the following colour is scattered most in atmosphere?

Two amplifiers having voltage gains 100 and 200 are connect in series. The overall gain of the amplifier is

In an electrical circuit, potential difference $V = (8.0 \pm 0.8)$ V and current $I = (2.0 \pm 0.2)$ A. The value of resistance $R$ with error limits is