問題一覧
1
What is the basis for declaring the direction of electric current is from positive terminal to negative terminal of a circuit?
Conventional
2
Which of the following will the effect of the electric shock in the human body depends on
Current flowing in the body
3
Which of the following conductors has the highest resistance?
Nichrome
4
In an American wire gauge (AWG) as the number gage increase the wire diameter?
decrease
5
A cylindrical copper rod has a resistance R. It is reformed to twice its original length with NO change in volume. What is the new resistance?
4R
6
Nine identical wires, each of diameter d and length L, are connected in series. The combination has the same resistance as a single similar wire of length L but whose diameter is
d/3
7
Suppose that the fundamental dimensions are taken to be force (F), velocity(V) and time(T). What are the dimensions of potential energy?
FVT
8
Resistor 1 has twice the resistance of resistor 2. They are connected in parallel to a battery. Find the ratio of thermal energy generation rate in resistor 1 to that of resistor 2.
1:2
9
What is the value of resistor with the color coded Green-Blue-Red-Gold?
5,600 ohms +5%
10
A car battery is rated at 80 amp-hr. An ampere-hour is a unit of ___.
Charge
11
Superposition theorem can be applied only to circuits having ____.
linear bilateral elements
12
“In any linear bilateral network, if a source of emf E in any branch produces a current I in any other branch, then same current I in the first branch”. The above statement in associated with?
reciprocity theorem
13
If an electrical network having one or voltage source, is transformed into equivalent electrical network with single current source (which is short circuit current of previous circuit) with parallel internal resistance of the network with all current source replaced by their internal resistance. The above illustration is called ___.
Norton’s Theorem
14
The coloumb force, F, acts on two charges a distance, r, apart. What is F proportional to?
1/r^2
15
Which statement about a charge placed in a dielectric material is TRUE?
The charge is confined to the region in which the charge was placed.
16
What will happen to an insulating medium with voltage more than breakdown voltage is applied?
it will get punctured
17
Permittivity is expressed in ____.
Farad/meter
18
The inverse capacitance is called ___.
Elastance
19
For which of the following parameter variation, the capacitance of the capacitor remains unaffected?
Thickness of the plates
20
At a dc steady state, capacitor looks like a/an ___ circuit and an inductor looks like a/an ___ circuit. I. Grounded II. Short III. Open
III and II
21
The time constant of an inductive circuit is defined as the ratio of
L/R
22
The time constant is the time it takes the current in an inductive circuit to rise to
63% of its final steady state value
23
In an RC circuit connected across dc source, which of the following is zero at the beginning of transient stage?
capacitor voltage
24
A capacitor having a capacitance of 3uf is connected across 200 Vdc source. The charging current will be least.
When capacitor is fully charged
25
The constant of a R-C circuit is defined as the time during which capacitor charging current becomes ____ percent of its ____ value.
37, initial
26
There is no transients in a pure resistive circuits because they ___.
have no stored energy
27
The transients current in a loss-free L-C circuit when excited from an ac source is a/an ____ sine wave.
undamped
28
A charged capacitor and an indicator are connected in series. At time t=0 the current is zero, but the capacitor is charged. If T is the period of the resulting oscillations, the next time after t=0 that energy stored in the magnetic field of the indicator is a maximum is.
T/4
29
A charged capacitor and an indicator are connected in series. At time t=0 the current is zero, but the capacitor is charged. If T is the period of the resulting oscillations, the next time after t=0 that energy stored in the electric field of the indicator is a maximum is.
T/2
30
Double energy transients are produced in the circuit consisting of ___.
resistance, inductance and capacitance
31
Transient current in an RLC circuit oscillatory decaying when
R < 2√L/C
32
The presence of electric current is only made known by the effect it produces. Three important effects are:
Heating, magnetic and electric shock
33
Out of the following, select the best conductor of electricity?
graphite
34
For a carbon-composition resistor. A resistance of 0.47 ohm will be represented by ____ stripes from left to right.
yellow, violet and silver
35
Electric pressure in an electric circuit is also called _____
voltage
36
What is the other term for American wire gauge?
brown and sharpe