Emt 1 PDF
Emt 1 PDF
Emt 1 PDF
Total points12/30
0 of 0 points
Password *
3333
12 of 30 points
Syllabus: Electric charge and Coulomb's law + Electric field
Ali
0/1
Fe < Fg
Fe> Fg
Fg < Fe
both b and c
Correct answer
both b and c
1/1
9.11 x 10^-31 C
6.25 x 10^18 C
1.6 x 10^-19 C
All of above
1/1
electric monopole
electric dipole
electric quadrupole
None of them
Correct answer
10^-8 Ohm meter
5) Elementary particle is
1/1
proton
neutron
electron
all
1/1
1/1
Microscopic
macroscopic
point charged
All
1/1
attractive
repulsive
both a and b
none
0/1
increases
decreases
maximizes
none of them
Correct answer
decreases
0/1
9.1 x 10 ^-27
8.85 x 10^-10
8.85 x 10^-12
8.85 x 10^-6
Correct answer
8.85 x 10^-12
0/1
+e
-e
+2e
zero
Correct answer
zero
12) Charge of neutron is
0/1
+2e
+e
-e
none
Correct answer
none
13) Two oppositely directed dipoles close to each other are called
0/1
electric dipole
electric monopole
electric quadrupole
all
Correct answer
electric quadrupole
0/1
Aluminum
copper
iron
all
Correct answer
all
0/1
Copper
glass
sand
aluminum
Correct answer
glass
1/1
13 x 10^ 12 C
13 x 10^13 C
13 x 10^ 14 C
13 x 10^ -13 C
17) SI unit of electric field is
0/1
N/C
V/m
N/m
both a and b
Correct answer
both a and b
1/1
one
two
three
infinity
1/1
negative charge
positive charge
both a and b
none
1/1
quantized
discrete
both a and b
none
0/1
P = q/m
P = q d^2
P=qd
all
Correct answer
P=qd
22) The electric field due to ring of charge is E = k q / Z ^2 . Ring behave as a point charge
when
0/1
Z << R
Z=R
Z >> R
All of above
Correct answer
Z >> R
0/1
left hand
right hand
vectors rule
both b and c
Correct answer
both b and c
0/1
0 degree
90 degree
180 degree
360 degree
Correct answer
180 degree
25) Potential energy will be ------ when electric field and dipole moment are anti parallel to
each other
0/1
Maximum
Minimum
Correct answer
Maximum
26) An electron is accelerated at 1.84 x 10^9 ms^-2 by electric field. What is the magnitude of
Electric field??
1/1
0.01 N/C
0.09 N/C
0.07 N/C
0.06N/C
0/1
Correct answer
6.88 x 10^-28 C-m
28) The regions between two charge where there is no electric field lines called
0/1
Positive zone
Negative zone
Neutral zone
None
Correct answer
Neutral zone
Uniform
Non uniform
Zero
Weak
0/1
E = 2F/qo
E = F/qo
E= Kq/r^2
Both b and c
Correct answer
Both b and c
This content is neither created nor endorsed by Google. - Terms of Service - Privacy Policy
Forms
0 of 0 points
Ali
Password *
800
5 of 30 points
Chapter : Gauss law + Electric potential
1) The electric flux through a surface will be ----- when vector area is held perpendicular to
electric field lines
0/1
Maximum
Minimum
Zero
Both b and c
Correct answer
Both b and c
2) In Gauss's law surface should be
0/1
Flat
Straight
Close
All of them
Correct answer
Close
0/1
Ampere law
Faraday law
Newton's law
None of them
Correct answer
None of them
0/1
Maximum
Minimum
Zero
Correct answer
Zero
5) A uniform charge spherical shell exerts no electrostatic ------ on charge particle placed
inside the shell
0/1
Charge
Force
Momentum
Velocity
Correct answer
Force
6) A surface encloses an electric dipole.what can you say about electric flux for this surface.
0/1
2 times increases
4 time increases
2 time decreases
Zero
Correct answer
Zero
0/1
All of them.
Correct answer
All of them.
8) The electric field just above the surface of the charged drum of photocopying machine has
magnitude of electric field 2.3 x 10 ^5 N/C. What is the surface charge density on the drum if it
is conductor.
0/1
3.2 x 10 ^-6
2.03 x 10 ^-6
Zero
4.8 x 10 ^-6
Correct answer
2.03 x 10 ^-6
9) A point charge of 1.84 micro Coloumb is at the center of cubicle Gaussian surface 55 cm
on edge. Find the flux through surface.
1/1
207909 Nm^2/C
207800 Nm^2/C
107909 Nm^2/C
Option 4
10) The net electric flux through each face of dice has magnitude in units of 10^3 Nm^2/C
equal to number N spots on face ( 1 through 6). The flux is inward for N odd and outward for
even. What is the net charge inside.
0/1
Zero
2.7 x 10^ -8 C
1.8 x 10^ -8 C
None of them
Correct answer
2.7 x 10^ -8 C
0/1
Magnitude of work
Sign of charge
Magnitude of charge
Sign of work
All of them
Correct answer
All of them
0/1
W/qo
2W/qo
W/2qo
Zero
Correct answer
Zero
0/1
Joule
Volt
J/C
Both b and c
Correct answer
Both b and c
0/1
Electric potential
Electric dipole
Correct answer
Electric dipole
0/1
Correct answer
2 dipole oriented anti parallel
16) The electric potential due to point charge varies 1/r term called
1/1
Monopole
Dipole
Quadrupole
All of them
0/1
V = k/q
V = kq/Z
V= kq/r^2
V= all of them
Correct answer
V = kq/Z
18) The family of surface that connect points having the same value of electric potential are
called
0/1
Closed surface
Gaussian surface
Equipotential surface
Both a and b
Correct answer
Equipotential surface
19) If potential is constant through out the region of space what will be the value of electric
field
0/1
E = kq/r
E = 2kq/r^2
Zero
Both b and c
Correct answer
Zero
20) What will be the potential difference b/w two conductor that carry like charge of same
magnitude
0/1
Maximum potential
Minimum potential
No potential
May be maximum may be minimum
Correct answer
No potential
1/1
No
Yes
Depends on medium
22) If you know E at a given point, What will be for the formula to calculate potential V at that
point
1/1
E = - dV/dr
E = kq/r
V = W/q
V= Vf - Vi
--e/3
+2e/5
+2e/3
+3e/2
Correct answer
+2e/3
24) If two up quarks and one quarks are placed at corner of equilateral triangle. What will be
the value of electric potential energy ?
0/1
U = W/q
U = kq/r
U = +2e/3
Zero
Correct answer
Zero
0/1
Joule
Electron volt
Both a and b
Volt
Correct answer
Electron volt
1/1
Scalar quantity
vector quantity
0/1
9.31 x 10^-6 J
1.6 x 10^-19 J
1.6 x 10^-19 C
None of them
Correct answer
1.6 x 10^-19 J
28) What must be the magnitude of an isolated positive point charge from the electric potential
at 15cm from the charge to be 120V.
0/1
1.6 x 10^-19 C
Zero
2 x 10^-9 C
3x 10^-18 C
Correct answer
2 x 10^-9 C
29) What is the electric potential at the surface of a gold nucleus? The radius is 7 x 10^-15 m
and atomic no. =79
0/1
Zero
Correct answer
1.6 x 10^7 volt
30) In the milikon oil drop experiment an electric field of 1.92 x 10^+5 N/C is maintained at
balance across two plates separated by 1.5 cm. Find Potential difference between plated?
0/1
880 volts
1880 volts
2880 volts
2800 volts
Correct answer
2880 volts
This content is neither created nor endorsed by Google. - Terms of Service - Privacy Policy
Forms
0 of 0 points
Ali
Password *
100
6 of 35 points
Chapters: 5 + 6 ( capacitors and dielectrics + Current and resistance)
Dear students Exercise Numerical are important. Most of the MCQs are taken from numerical problem
according to university pattern.
0/1
DC, AC
AC, DC
AC, AC
DC, DC
Correct answer
AC, DC
1/1
Discharges
Charges
Both a and b
None of them
0/1
Area of plates
Separation of plates
Dielectric medium
All of these
Both a and c
Correct answer
All of these
0/1
Remains constant
Increases
Decreases
None of them
Correct answer
Increases
5) Capacitance of cylindrical capacitor depends
0/1
All of these
Both a and c
Correct answer
All of these
1/1
7) When the potential difference and electric field between the plate of capacitor rises then
amount of charge stored in a capacitor
0/1
Decreases
Increases
Remains constant
Correct answer
Increases
8) A typical system of 10000 capacitors can store -------- energy which is sufficient to start
nuclear --------- reaction.
0/1
40 x 10^6 J , fusion
40 x 10^5 J, fission
60 x 10^6 J, fusion
60 x 10^4 J, fission
Correct answer
60 x 10^6 J, fusion
0/1
Mica
Paper
Plastic
Glass
All of them
Correct answer
All of them
0/1
All of them
Both a and b
Correct answer
All of them
0/1
Remains constant
Increases
Decreases
None of them
Correct answer
Increases
1/1
13) What is the capacitance of earth, viewed as an isolated conducting sphere of radius 6370
km.
0/1
7.1 x 10^6 F
9 x 10^-4 F
7.1 x 10^-4 F
7.9 x 10^2 F
Correct answer
7.1 x 10^-4 F
14) The plates of a parallel plate capacitor is separated by a distance d = 1 mm. what must be
the plate area if the capacitance is to be 1 micro farad
0/1
12 m^2
82 m^2
112 m^2
200 m^2
Correct answer
112 m^2
15) How much energy is stored in 2.0 m^3 of air due to the fair weather electric field of
strength 150 V/m.
0/1
U = 2 x 10^2 J
U = 0.12 J
U = 12 X 10^-1
U = 2.0 x 10^-7 J
Correct answer
U = 2.0 x 10^-7 J
16) An isolated metal sphere whose diameter is 12.6 cm has potential of 8150 V. Calculate
energy density in electric field near the surface of sphere.
0/1
74 J/m^3
0.074 J/m^3
12 J/m^3
0.012 J/m^
Correct answer
0.074 J/m^3
17) How many 1.0 micro farad capacitors must be connected in parallel to store a charge of
one coulomb with potential of 110 V across the capacitors?
0/1
1000
9000
9090
5000
Correct answer
9090
1/1
Free electrons
Ions
Both a and b
None of them
0/1
10^-6 m/s
10^-5 m/s
10^-4 m/s
10^-3 m/s
Correct answer
10^-3 m/s
0/1
Correct answer
1.7 x 10^-7 ohm meter
21) By increasing length of wire 2 times. What will be the effect on resistance of wire.
0/1
Remains same
Increases 2 times
Increases 4 times
Decreases 4 times
Decreases 2 times
Correct answer
Increases 4 times
0/1
One
Two
Three
Four
Correct answer
Two
E=Jk
E = J/m
E = Jβ
E = Jρ
Correct answer
E = Jρ
0/1
Ohm’s law
Coulomb’s law
Joule’s law
Laplace equations
Correct answer
Joule’s law
0/1
2.6 MJ
3.6 MJ
3.6 KJ
2.6 KJ
Correct answer
3.6 MJ
0/1
Joule’s law
Newtons law
Ohm’s law
Coulomb law
Correct answer
Ohm’s law
0/1
7.2 K
1.18 K
163 K
4.2 K
Correct answer
7.2 K
28) Barium copper oxide becomes super conductor at temperature
0/1
1.18 K
3.72 K
4.2 K
163 K
Correct answer
163 K
29) Is filament resistance lower or higher in a 500 W light bulb than in a 100 W bulb when
both are designed to operate at 200 V
0/1
R(500) = R(100)
R(500) < R(100)
Correct answer
R(500) < R(100)
30) A strip of silicon of width W = 3.2 mm and thickness d = 250 micro meter carries a current
of 190 Ma. In this case n = 8 x 10^21 electrons/m^3 . What is drift velocity
0/1
100 m/s
185 m/s
200 m/s
285 m/s
Correct answer
185 m/s
31) You are given a nichrome wire of resistance 144 ohm. The wire is cut into half and the two
halves are connected in parallel across 240 V line. Calculate the power dissipated.
0/1
36 W
400 W
220 W
1600 W
0W
Correct answer
1600 W
32) A steel trolley car rail has a cross sectional area of 56 cm^2 . What is the resistance of 11
km of rail. The resistivity of steel is 3 x 10^-7 ohm meter.
1/1
58 x 10^-1 ohm
0.48 ohm
100 ohm
33) The copper windings of a motor have a resistance of 50 ohm at 20 degree when the motor
is idle. After running for several hour the resistance rises to 58 ohm. What is the temperature
od the windings of a motor?
0/1
12 degree C
50 degree C
57 degree C
273 degree C
Correct answer
57 degree C
34) A student 9V and 7.5W portable radio was left on from 9.00 pm until 3:00 am. How much
charge passes through the wire
1/1
17928 C
19728 C
17600 C
None of these.
35) A cylindrical resistor of radius 5.12 mm and length 1.96 cm is made of material that has
resistivity of 3.5 x 10^-5 ohm meter. What is current density? Power dissipation is 1.55 W.
0/1
13.7 A/m^2
16500 A/m^2
165222.5 A/m^2
16533.6 A/m^2
Correct answer
165222.5 A/m^2
This content is neither created nor endorsed by Google. - Terms of Service - Privacy Policy
Forms
0 of 0 points
Ali
Password *
50
9 of 30 points
Syllabus: DC Circuit + Magnetic field effects
0/1
Potential force
Electromotive force
electric force
chemical force
Correct answer
Electromotive force
0/1
Ohm's
Maxwell
Kirchhoff
Faraday
Correct answer
Kirchhoff
0/1
ammeter
voltmeter
galvanometer
potentiometer
Correct answer
potentiometer
0/1
positive
negative
no change
Correct answer
negative
5) When no current is drawn through a battery then emf is
0/1
zero
not zero
Equal to Vt
none of these
Correct answer
not zero
1/1
0/1
None of them
Correct answer
Law of conservation of energy
0/1
No node no branch
Correct answer
No node no branch
0/1
RL
time
L/R
All of them
Both b and c
Correct answer
Both b and c
10) In growth of charge and growth of current in RC series circuit which one is
true at t =0
0/1
Correct answer
P.d across capacitor is zero
11) 7Time constant is defined as the time during which a capacitor charges to -
---- of its equilibrium value
0/1
63%
0.63 times
37%
Both a and b
Correct answer
Both a and b
12) If time consrant in RC circuit is small, the capacitor is charged or
discharged
1/1
Slowly
Rapidly
At constant rate
None of these
0/1
Postive
Negative
Zero
Remains constant
Correct answer
Negative
0/1
To decrease net voltage batteries are connected in series
None of these
Correct answer
To increases net voltage batteries are connected in series
15) A 5.12 A current i set up in external circuit by a 6V battery for 5.75 min. By
how much is the chemical energy of the battery reduced
0/1
10876 J
10800 J
10598 J
10900 J
Correct answer
10598 J
1/1
4.5 A
6A
9A
11 A
17) How many times constants must elaspe before a capacitor in an RC circuit
is charged to within 1% of its equilibrium charge.
0/1
t = 9 tc
t = 4 tc
t = 4.6 tc
t = 5 6 tc
Correct answer
t = 4.6 tc
1/1
Motion of magnet
Motion of charge
All of these
19) A current carrying conductor experience maximum magnetic force in a
uniform magnetic field when it is placed
1/1
0/1
Correct answer
Repel each other
21) Which of the following particle moving in the magnetic field cannot be
deflected.
0/1
Alpha particle
Beta particles
Electrons
Neutron
Correct answer
Neutron
22) When an electron enter in a magnetic field, right angle to its motion, then
the magnitude of velocity will be
1/1
Changed
Unchanged
Zero
None of these
1/1
Electric force
Magnetic force
Gravitational force
Nuclear force
24) E/B has the same dimension as that of
0/1
Force
Momentum
Charge
Velocity
Correct answer
Velocity
1/1
1/1
Zero
Maximum
ILB Sina
IBA Cosa
0/1
C/T
Kg/T
J/T
None of them
Correct answer
J/T
28) The magnetic potential energy will be ---- when magnetic dipole moment and
magnetic field B are parallel
0/1
Maximum
minimum
Correct answer
minimum
29) An electron in uniform magnetic field has a velocity V = 40 i + 35 j km/s
experience a force F = (-4.2 i + 4.8 j) N. If Bx = 0, calculate the magnitic field
0/1
-0.75 j
-0.75 i
-0.75 k
Correct answer
-0.75 k
30) At a place earth, s magnetic field is 39.0 micro Tesla and it is horizontal
due to north. Calculate magnetic force on a conductor of length 1 m carrying
current of 10mA due east.
0/1
4 x 10^6 N
4 x 10^7 N
3.9 x 10^-7 N
3.9 x 10^7 N
Correct answer
3.9 x 10^-7 N
This content is neither created nor endorsed by Google. - Terms of Service - Privacy Policy
Forms
0 of 0 points
Ali
Password *
900
3 of 25 points
Ampere's law + Faraday law of EM induction
1/1
0/1
Uniform
Weak
Zero
None of them
Correct answer
Weak
3) In a Bohr model of hydrogen atom, the electron circulate around the nucleus in pathb 5.29
x 10^-11 m at frequency 6.6 x 10^15 Hz. What is the value of "B" at the center of orbit?
0/1
10 T
11 T
12 T
13 T
Correct answer
13 T
4) A surveyor is using a magnetic compass 6.3 m below a power line in which there is a
steady current of 120 A. Will this interface seriously with the compass reading. The horizontal
component of earth magnetic field at the site is 21 micro Tesla.
0/1
Correct answer
3.8 micro Tesla
5) A solenoid has 100 turns per centimeter. An electron moves within the solenoid in a circle
of radius 2.3 cm perpendicular to axis of solenoid. If speed of electron is 0.046c. Find the
current.
0/1
0.10 A
0.27 A
0.37 A
0.90 A
Correct answer
0.27 A
6) A solenoid is 1.5 m long carries a current of 18 A. The magnetic field inside it is 22.5 mT.
Find the total number of turns of the solenoid
0/1
1293
1393
1493
1593
Correct answer
1493
7) A solenoid of certain diameter is 3.14 m long. It has 5 layers and 850 turns each and
carries a current 5A. What is B at the center.
1/1
8.5 x 10^-3 T
8.5 x 10^-5 T
8.3 x 10-1 mT
9.3 x 10^-3 T
8) 1 volt is equal to
0/1
Wb/T
Wb/s
J/C
All of them
Both b and c
Correct answer
Both b and c
9) An automobile having a radio atenna 110 cm long travels 90 km/h in a region where
magnetic field is 55 micro Tesla. Find the value of induced emf
0/1
0.5 mV
1.5 mV
2.5 mV
3.5 mV
Correct answer
1.5 mV
10) The armatures of a motor 97 turns of area 190 cm^2 and rotates in a uniform magnetic
field of 0.33 T. A Pd of 24 V is applied. If no load is attached and friction is neglected. Find the
rotational speed at equilibrium
0/1
10 rad/s
20 rad/s
30 rad/s
40 rad/s
Correct answer
40 rad/s
11) A uniform magnetic field is normal to the plane of a circular loop 10.4 cm in diameter
made of copper wire ( R = 1.12 x 10^-3 Ohm) . At what rate must the magnetic field change
with time if an induced current of 9.66 A is to appear in the loop.
0/1
1.27 T/s
0.75 T/s
112.2 T/s
95.7 T/s
Correct answer
1.27 T/s
0/1
Mass
Charge
Momentum
Energy
Correct answer
Energy
13) If the length of a conductor placed parallel to the magnetic field is doubled, the induced
emf
1/1
Becomes double
Reduces to half
Zero
Remains constant
0/1
Both a and b
Correct answer
Using a strong magnetic fields
15) Current can be induced in a coil by changing the area of the coil in a
0/1
None of these
Correct answer
Constant magnetic field
16) The current flowing through the coil due to induced emf in it, depends upon
0/1
All of them
Correct answer
Resistance of the coil
0/1
Correct answer
Directions of induced current
18) A mettalic ring is attached to wall of the room. When the north pole of bar magnet is
brought near the ring, the induced current in the ring is
0/1
Zero
Infinite
Correct answer
In anti clock wise
0/1
Weber / m^2
Weber
Weber/Am
Weber/Am^2
Correct answer
Weber/Am
0/1
Toroid
Solenoid
Both a and b
None of these
Correct answer
Solenoid
21) The magnetic field in a certain region is given by B = 40i - 18j. How much flux passes a
5.0 cm^2 area loop in this region if the loop lies flate in the x-y plane.
0/1
90 x 10^-4 Wb
200 x 10^-4 Wb
110 x 10^-4 Wb
Zero
Correct answer
Zero
22) When current passes through a solenoid coil, it behaves like a
0/1
Circular maagnet
Bar magnet
North pole
None of these
Correct answer
Bar magnet
23) Which of the following is most suitable for the core of electromagnetic
0/1
Air
Steel
Soft iron
An alloy
Correct answer
Soft iron
0/1
Correct answer
Attract each other
0/1
Both a and b
Correct answer
Right hand grip rule
This content is neither created nor endorsed by Google. - Terms of Service - Privacy Policy
Forms
Password *
200
Ali
9 of 30 points
Magentic properties of matter + Inductance
0/1
none of them
Correct answer
mono pole does not exist
Correct answer
5.02 X 10^-27 J/T
3) What is the range of [K(m) - 1 ] for most of the non-ferromagnetic material. Where K(m) is
permeability constant of material
1/1
10^-3 to 10^-6
10^-2 to 10^-6
10^-2 to 10^-4
10^-3 to 10^-4
0/1
Fe = 1388 and Co = 85
Fe = 1043 and Co = 85
Fe = 1388 and Co = 670
Fe = 1043 and Co = 1388
Correct answer
Fe = 1043 and Co = 1388
0/1
Iron
sodium
steel
copper
Correct answer
Iron
0/1
ferro magnetic
par magnetic
dia magnetic
conductor
Correct answer
dia magnetic
7)Which one has the least hysteresis area
0/1
steel
wrought iron
soft iron
cobalt
Correct answer
soft iron
0/1
saturation
retentivity
hysteresis
corecivity
Correct answer
hysteresis
1/1
ferro magnetic material
paramagnetic material
semi conductor
0/1
steel
iron
copper
alumanium
Correct answer
steel
0/1
para magnetic
dia magenetic
ferro magnetic
not effected
Correct answer
para magnetic
12) The material of a permanent magnet has
0/1
Correct answer
high retentivity, high coercivity
0/1
hammereing it
heating it
all of above
Correct answer
all of above
1/1
magnetic energy density
thermal energy per unit volume
1/1
strong magnet
small magnet
both a and b
none of these
16) When the current is reduced to zero and the material remains magnetized, this property is
called
1/1
coercivity
retentivity
saturation
hysteresis
17) In the electrical circuit acts Inductor acts as a
0/1
capacitor
resistance
choke
battery
Correct answer
choke
18) In growth of current in R-L series circuit. the current is maximum at time = ---
1/1
infinity
zero
both a and c
0/1
50%
33%
37%
63%
Correct answer
37%
0/1
Henery
Vs/A
Jt/m
Wb/m^2
both a and b
Correct answer
both a and b
0/1
capacitor
energy
resistance
current
none of them
Correct answer
none of them
22) A solenoid has inductance 53 m H and a resistance of 0.37 ohm so L/R = 0.143 h/Ohm .IF
it is connected to battery , how long will it make for the current to reach one half of its final
equilibrium value
0/1
t = 3 sec
t = 2 sec
t = 10 sec
t = 0.10 sec
Correct answer
t = 0.10 sec
23) Compare the energy required to set-up in a cube 10 cm on edge, Electric field 1.0 x 10^5
V/m and uniform magnetic field is 1.0 T
0/1
Um/Ue = 10 x 10^5
Um/Ue = 8 x 10^6
Um/Ue = 8 x 10^10
Correct answer
Um/Ue = 8 x 10^6
24) A solenoid 126 cm long is formed by 1870 windings carrying a current of 4.36 A. The core
of solenoid is filled with iron and effective permeability constant 968. Calculate the inductance
of solenoid whose diameter is 5.45 cm
0/1
2.8 H
3.8 H
7.8 H
9.8 H
Correct answer
7.8 H
25) The current is RL series circuit builds up to one third of its steady state value in 5.22 sec .
calculate the inductive time constant
0/1
10.8 sec
12.8 sec
14.8 sec
18.8 sec
Correct answer
12.8 sec
26) The current in RL series circuit drops from 1.16 A to 10.2 m A in 1.50 sec immediately
removal of the battery from the circuit. If L = 9.44 H. Find the resistance
1/1
30 Ohm
40 Ohm
100 Ohm
0 Ohm
None of them
27) A 45 Volt P.D is suddenly applied to a coil with L = 50 m H and R = 180 Ohm. at what rate
is current increasing after 1.2 ms.
0/1
1 A/s
2 A/s
10 A/s
12 A/s
Correct answer
12 A/s
28) A 92 m H toroidal inductor encloses a volume of 0.022 m^3 , if the energy density is 71
mJ/m^3 . Calculate the current
1/1
0.144 A
0.184 A
1.044 A
1.184 A
29) The magnetic field in the inter-stellar space of our galaxy has a magnitude of about 100
pT. calculate the corresponding energy density in eV/cm^3
0/1
20000
25000
30000
35000
Correct answer
25000
1/1
all of these
This content is neither created nor endorsed by Google. - Terms of Service - Privacy Policy
Forms
Physics EMT Ch 13+14
Total points8/30
0 of 0 points
Ali
Password *
600
8 of 30 points
Alternating current circuit + Maxwell equations
1) The only difference between construction of D. c and an A.C generator is that of
0/1
Carbon brushes
Armature
Commutator
Magnetic field
Correct answer
Commutator
0/1
Two
Three
Four
One
Correct answer
Four
0/1
Heat loss
Step up process
Induction phenomenon
Correct answer
Heat loss
0/1
Decreasing area
Correct answer
Increasing area of coil
5) In A.C generator when plane of coil is perpendicular to the magnetic field, then output of
generator is
0/1
Nw AB
2 pie f
Maximum
Zero
Correct answer
Zero
6) A transformer
1/1
Works on A. C only
Works on D. C only
None of these
7) If a step up transformers were 100% efficient, the primary and secondary windings would
have the same
0/1
Current
Power
Voltage
Directions of windings
Correct answer
Power
8) Turn ratio of a transformer is 50. If 220 V AC is applied to its primary coil, voltage in
secondary coil will be
0/1
440 V
4.4 V
220 V
11000 V
Correct answer
11000 V
1/1
Input voltage
Core of transformers
Resistance of coil
0/1
Zero degree
90 degree
180 degree
270 degree
Correct answer
Zero degree
0/1
Large
Small
Infinite
Zero
Correct answer
Large
0/1
Square root of 2 A
2A
2 /sq root of 2
None
Correct answer
Square root of 2 A
13) The slope of q-t curve at any instant of time gives
1/1
Current
Voltage
Charge
Both A and B
14) The reactance of an inductor at 50Hz is 10 Ohm its reactance at 100Hz becomes
1/1
20 Ohm
5 Ohm
2.5 Ohm
1 Ohm
1/1
Infinite
Zero
Minimum
Maximum
1/1
Low frequency
High frequency
Zero frequency
Negative frequency
0/1
Ohm
mho
siemen
Both b and c
Both a and b
Correct answer
Both b and c
XL < Xc
XL > Xc
Z < Xc
XL = Xc
Correct answer
XL = Xc
0/1
Second
Ampere
Hertz
Farad
Correct answer
Second
0/1
Zero
Minimum
Maximum
Moderate
Correct answer
Minimum
0/1
Infinite
1/2
Correct answer
1
22) In an inductive circuit L= 230mH, f= 60Hz, VoL = 36V. Find current amplitude in circuit
0/1
0.1 A
0.3 A
0.4 A
0.5 A
Correct answer
0.4 A
23) At what frequency would a 6.23 mH inductor and 11.4 micro farad capacitor have the
same reactance?
1/1
500 Hz
598 Hz
600 Hz
678 Hz
24) The resonance frequency of RLC series circuit is 86 Hz. If C=15micro Farad, find the
inductance.
0/1
229 H
22.9 H
2.29 H
0.229 H
Correct answer
0.229 H
25) A generator supplies 150Volt to the primary coil of a transformer of 65 turns. If the
secondary coil has 780 turns, what is the secondary voltage.
0/1
2200 volt
3000 volt
1800 volt
1200 volt
Correct answer
1800 volt
0/1
Ampere law
Correct answer
Gauss law for electricity
0/1
All of them
Correct answer
Magnetic mono pole does not exist
0/1
Correct answer
B
0/1
Div(I) = H
Div(H) = J
Curl(H)=J
Curl(B) =D
Correct answer
Curl(H)=J
30) In which of the following forms Maxwell equations cannot be represented
1/1
Static
differential
integral
Harmonic
This content is neither created nor endorsed by Google. - Terms of Service - Privacy Policy
Forms