JEE Physics Test Series Quiz-2

In a npn transistor circuit, the collector current is \(10 \mathrm{~mA}\). If 95 percent of the electrons emitted reach the collector, which of the following statements are true?

The amplifiers \(\mathrm{X}, \mathrm{Y}\) and \(\mathrm{Z}\) are connected in series. If the voltage gains of \(X, Y\) and \(Z\) are 10,20 and 30, respectively and the input signal is \(1 \mathrm{mV}\) peak value, then what is the output signal voltage (peak value) if dc supply voltage is \(10 \mathrm{~V}\)?

Two car garages have a common gate which needs to open automatically when a car enters either of the garages or cars enter both. Which logic gate defines this?

A Zener of power rating \(1 \mathrm{~W}\) is to be used as a voltage regulator. If zener has a breakdown of \(5 \mathrm{~V}\) and it has to regulate voltage which fluctuated between \(3 \mathrm{~V}\) and \(7 \mathrm{~V}\), what should be the value of \(R_s\) for safe operation (Fig. below)?

If each diode in Fig. below has a forward bias resistance of \(25 \Omega\) and infinite resistance in reverse bias, what will be the values of the current \(I_1, I_2, I_3\) and \(I_4\)?

In the circuit shown in Fig. below, when the input voltage of the base resistance is \(10 \mathrm{~V}, \mathrm{~V}_{b e}\) is zero and \(\mathrm{V}_{\mathrm{ce}}\) is also zero. Find the values of \(I_{\mathrm{b}}, I_{\mathrm{c}}\) and \(\beta\).

Draw the output signals \(C_1\) in the given combination of gates (Fig. below).

When a diode is forward biased, it has a voltage drop of \(0.5 \mathrm{~V}\). The safe limit of current through the diode is \(10 \mathrm{~mA}\). If a battery of emf \(1.5 \mathrm{~V}\) is used in the circuit, the value of minimum resistance to be connected in series with the diode so that the current does not exceed the safe limit is:

If a semiconductor photodiode can detect a photon with a maximum wavelength of \(400 \mathrm{~nm}\), then its band gap energy is Planck’s constant, \(h=6.63 \times 10^{-34} \mathrm{~J}\).s.
Speed of light, \(\quad c=3 \times 10^8 \mathrm{~m} / \mathrm{s}\)

The current \(i\) in the network is:

Two identical capacitors A and B, charged to the same potential \(5 \mathrm{~V}\) are connected in two different circuits as shown below at time \(t=0\). If the charge on capacitors \(\mathrm{A}\) and \(\mathrm{B}\) at time \(t=C R\) is \(\mathrm{Q}_{\mathrm{A}}\) and \(\mathrm{Q}_{\mathrm{B}}\) respectively, then (Here \(e\) is the base of natural logarithm)

In the figure, potential difference between \(A\) and \(B\) is:

The circuit shown below contains two ideal diodes, each with a forward resistance of \(50 \Omega\). If the battery voltage is \(6 \mathrm{~V}\), the current through the \(100 \Omega\) resistance (in Amperes) is:

The mobility of electrons in a semiconductor is defined as the ratio of their drift velocity to the applied electric field. If, for an n-type semiconductor, the density of electrons is \(10^{19} \mathrm{~m}^{-3}\) and their mobility is \(\left.1.6 \mathrm{~m}^2 / \mathrm{V}. \mathrm{s}\right)\) then the resistivity of the semiconductor (since it is an n-type semiconductor contribution of holes is ignored) is close to:

The forward-biased diode connection is: 

Which of the following statements is not true?

A full-wave rectifier circuit along with the output is shown in Figure below. The contribution (s) from the diode 1 is (are)

The probability of electrons to be found in the conduction band of an intrinsic semiconductor at a finite temperature

In a \(p-n\) junction diode not connected to any circuit,

Holes are charge carriers in

The impurity atoms with which pure silicon should be doped to make a p-type semiconductor are those of

Identify the correct output signal \(\mathrm{Y}\) in the given combination of gates (as shown) for the given inputs A and \(B\).

Identify the operation performed by the circuit given below:

In the following digital circuit, what will be the output at ‘ \(Z\) ‘, when the input \((A, B)\) are \((1,0),(0,0),(1,1),(0,1)\) :

Boolean relation at the output stage- Y for the following circuit is:

In the given circuit, the value of Y is:

The output of the given logic circuit is:

If a, b, c, d are inputs to a gate and x is its output, then, as per the following time graph, the gate is:

The truth table for the circuit given in the Figure is :

To get output ‘ 1 ‘ at \(\mathrm{R}\), for the given logic gate circuit the input values must be:

The charge on a capacitor plate in a circuit, as a function of time, is shown in the figure:

What is the value of current at \(t=4 \mathrm{~s}\)?

A uniform wire of length \(l\) and radius \(\mathrm{r}\) has a resistance of \(100 \Omega\). It is recast into a wire of radius \(\frac{r}{2}\). The resistance of the new wire will be:

In the given circuit diagram, a wire is joining points B and D. The current in this wire is:

A uniform metallic wire has a resistance of \(18 \Omega\) and is bent into an equilateral triangle. Then, the resistance between any two vertices of the triangle is:

In the given circuit all resistances are of value \(R \mathrm{~ohm}\) each. The equivalent resistance between \(A\) and \(B\) is:

In the given circuit diagram when the current reaches steady state in the circuit, the charge on the capacitor of capacitance \(\mathrm{C}\) will be :

In the below circuit, the current in each resistance is

Six equal resistances are connected between points \(\mathrm{P}, \mathrm{Q}\) and \(R\) as shown in the figure. The net resistance will be maximum between:

The effective resistance between points \(P\) and \(Q\) of the electrical circuit shown in the figure is

Find out the value of current through \(2 \Omega\) resistance for the given circuit.

An infinite ladder network of resistances is constructed with a \(1 \mathrm{ohm}\) and \(2 \mathrm{ohm}\) resistances, as shown in the figure below.

The 6 volt battery between A and B has negligible internal resistance :
What is the effective resistance between A and B?

The equivalent resistance between points \(A\) and \(B\) of the circuit given below is …… \(\Omega\).

In the following circuit, the current through the resistor \(R(=2 \Omega)\) is \(I\) amperes. The value of \(I\) is

In the circuit shown below, each battery is \(5 \mathrm{~V}\) and has an internal resistance of \(0.2 \mathrm{ohm}\).

The reading in the ideal voltmeter \(V\) is ….. Volt.

The circuit shown here has two batteries of \(8.0 \mathrm{~V}\) and 16.0 V and three resistors \(3 \Omega, 9 \Omega\) and \(9 \Omega\) and a capacitor of \(5.0 \mu \mathrm{F}\).

How much is the current \(I\) in the circuit in steady state?