Physics Practice MCQs

1-The relation (B. L)I=UI is called
a-Amperes law b-Ohm’s law
c-Gauss’s law d-Newton’s law

2-(B. L)i is equal to
a-UI b=UNI
c-UNI/2r d-U/I

3-The magnetic field of induction of Toroid is
a-UNI/2r b-UI/2r
c-U2r/NI d-2r/UI

4-The magnetic field of induction of solenoid is
a-Uin b-UI
c-Uin/2r d-2r/UnI

5- is a coil of an insulated copper wire
wound on a long cylinder.
a-solenoid b-Toroid
c-Battery cell d-Hollow cylinder

6- is a coil of an insulated copper wire
wound on a circular shape material.
a-Toroid b-Solenoid
c-Circuit d-Potentiometer

7-The dot product between tangential components
And the summation of all the components of length
is equal to product of and
a-U and I b-U and N
c-U and V d-U and R

8- (B. L)=UI here U is called
a-Permeability of free space
b-Permitivity of free space
c-Relative permitivity
d-Di-electric constant

9-The value of U is
a-4*10^-7weber/A.m b-4*106-7weber/A.m
c-4*10^-7weber/C.m d-4*10^7coulomb/weber.m

10-The unit of B is
a-Weber b-Coulomb
c-Ampere d-Ohm

11-Acording to Biot and Savart law the magnetic field
of induction is directly related with
a-Twice of the current.
b-Twice of the voltage.
c-Twice of the resistance.
d-Thrice of the voltage.

12-What does the relation B2I/r represents.
a-Biot and Savart law b-Faraday law
c-Lenz law d-Inverse square law

13-Acording to Biot and Savart law the magnetic field
of induction B is related to
a-1/r b-r
c-r^2 d-i/r^2

14-Acording to Biot and Savart law the equation
B=(constant)2I/r here constant is
a-U/4 b-4U/
c-U/4r d-4r/U

15- l=Circumference of a circle which is equal to
a-2r b-2r^2
c-r^2 d-4/3 r^3

16-The magnetic field of induction will be maximum
If
a-B and L are in same direction.
b-B and L are in opposite direction.
c-B and L are perpendicular.
d-B is zero

17-Ampere’s law was proposed by
a-Ampere b-Faraday
c-Newton d-Coulomb

18-Ampere’s law carries which variable quantity.
a-I b-V
c-R d-C

19-The magnetic field of induction will be minimum if
a-B and L are in same direction.
b-B and L are in opposite direction.
c-B and L are perpendicular.
d-B is zero

20-Magnetic flux are the lines of forces around a
a-charge b-magnet
c-electron d-positron

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Modulus of Rigidity

Modulus of Rigidity:
In materials science, modulus of rigidity or shear modulus is defined as the ratio of shear stress to the shear strain. The rigidity modulus is one of several quantities for measuring the strength of materials. All of them arise in the generalized Hooke's law:
Young's modulus describes the material's response to linear strain (like pulling on the ends of a wire),
The bulk modulus describes the material's response to uniform pressure.

This modulus is concerned with the deformation of a solid when it experiences a force parallel to one of its surfaces while its opposite face experiences an opposing force (such as friction).

Description:

The apparatus consists of a rod clamped at one end and attached to a wheel at the other. The rod passes through a bearing at the wheel end and known torques may be applied by a string wrapped around the wheel. The twist in the rod is measured with an angular scale.

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Semiconductor Diode

Semiconductor Diode:

The most common kind of diode in modern circuit design is the semiconductor diode, although other diode technologies exist. The semiconductor diode is cut from a single crystal of a semiconductor material (such as silicon or germanium) to which special impurities has been added during manufacture so that the crystal is now composed of two distinct regions. One region contains semiconductor material of the p-type, which contains more positive charge carriers than negative; the other contains material of the n-type, which has more negative charge carriers than positive. The region of contact between the two types is called the p–n junction (depletion layer), and it is this that acts as the barrier preventing current from flowing.

The semiconductor diode has the valuable property that electrons only flow in one direction across it and as a result it acts as a rectifier. As it has two electrodes it receives its name - diode. In view of this, it is one of the most fundamental structures in semiconductor technology. The bipolar junction transistor, junction FET and many more all rely on the PN junction for their operation. This makes the semiconductor PN junction diode one of the key enablers in today's electronics technology.

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