A particle is moving with constant speed in a circular path. When the particle turns by an angle $$90^{\circ }$$, the ratio of instantaneous velocity to its average velocity is $$\pi :x\sqrt{2}$$. The value of $$x$$ will be -

A small block of mass $$100\mathrm{g}$$ is tied to a spring of spring constant $$7.5\mathrm{N}/\mathrm{m}$$ and length $$20\mathrm{cm}$$. The other end of spring is fixed at a particular point A. If the block moves in a circular path on a smooth horizontal surface with constant angular velocity $$5\mathrm{rad}/\mathrm{s}$$ about point $$\mathrm{A}$$, then tension in the spring is -

As shown in the figure, a particle is moving with constant speed $$\pi \mathrm{m}/\mathrm{s}$$. Considering its motion from $$\mathrm{A}$$ to $$\mathrm{B}$$, the magnitude of the average velocity is :

A child of mass $$5\mathrm{kg}$$ is going round a merry-go-round that makes 1 rotation in $$3.14\mathrm{s}$$. The radius of the merry-go-round is $$2\mathrm{m}$$. The centrifugal force on the child will be

Choose the correct statement about Zener diode :

Given below are two statements : Statement I: In a typical transistor, all three regions emitter, base and collector have same doping level. Statement II: In a transistor, collector is the thickest and base is the thinnest segment. In the light of the above statements, choose the most appropriate answer from the options given below.

Match List I with List II: .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; overflow:hidden;padding:10px 5px;word-break:normal;} .tg th{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; font-weight:normal;overflow:hidden;padding:10px 5px;word-break:normal;} .tg .tg-amwm{font-weight:bold;text-align:center;vertical-align:top} .tg .tg-0lax{text-align:left;vertical-align:top} List I List II A. Intrinsic semiconductor I. Fermi-level near the valence bond B. n-type semiconductor II. Fermi-level in the middle of valence and conduction band. C. p-type semiconductor III. Fermi-level near the conduction band D. Metals IV. Fermi-level inside the conduction band Choose the correct answer from the options given below :

The effect of increase in temperature on the number of electrons in conduction band ($${\mathrm{n}}_{\mathrm{e}}$$) and resistance of a semiconductor will be as:

The output $Y$ for the inputs $A$ and $B$ of circuit is given by Truth table of the shown circuit is:

The output waveform of the given logical circuit for the following inputs A and B as shown below, is :

For the given logic gates combination, the correct truth table will be

Which one of the following statement is not correct in the case of light emitting diodes? A. It is a heavily doped p-n junction. B. It emits light only when it is forward biased. C. It emits light only when it is reverse biased. D. The energy of the light emitted is equal to or slightly less than the energy gap of the semiconductor used. Choose the correct answer from the options given below:

Statement I : When a Si sample is doped with Boron, it becomes P type and when doped by Arsenic it becomes N-type semi conductor such that P-type has excess holes and N-type has excess electrons. Statement II : When such P-type and N-type semi-conductors, are fused to make a junction, a current will automatically flow which can be detected with an externally connected ameter. In the light of above statements, choose the most appropriate answer from the options given below

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R Assertion A : Photodiodes are used in forward bias usually for measuring the light intensity. Reason R : For a p-n junction diode, at applied voltage V the current in the forward bias is more than the current in the reverse bias for $$|{\mathrm{V}}_{\mathrm{z}}|>\pm \mathrm{v}\ge |{\mathrm{v}}_0|$$ where $${\mathrm{v}}_0$$ is the threshold voltage and $${\mathrm{V}}_{\mathrm{z}}$$ is the breakdown voltage. In the light of the above statements, choose the correct answer from the options given below

The logic gate equivalent to the given circuit diagram is :

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R Assertion A : Photodiodes are preferably operated in reverse bias condition for light intensity measurement. Reason R : The current in the forward bias is more than the current in the reverse bias for a $$p-n$$ junction diode. In the light of the above statements, choose the correct answer from the options given below :

In the given circuit, the current (I) through the battery will be

The output from NAND gate having inputs A and B given below will be,

For the following circuit and given inputs A and B, choose the correct option for output '$$Y$$'

In an n-p-n common emitter (CE) transistor the collector current changes from 5 $$\mathrm{mA}$$ to $$16\mathrm{mA}$$ for the change in base current from $$100\mu \mathrm{A}$$ and $$200\mu \mathrm{A}$$, respectively. The current gain of transistor is __________.