MCQ
4961. Two equal resistances are connected in series across a certain supply. If the resistances are now connected in parallel, the power produced will become-
two-times
four times
one-half
one-fourth
4962. What will be the current in 2 seconds from a wire of having 10 mC charge flow and 2.5mm cross sectional area?
25mA
5mA
20mA
4mA
4963. Suppose, double the voltage in a simple de circuit and cut the resistance in half, then the current will-
Become four times as great
Become twice as great
Stay the same as it was before
Become half as great
4964. The total resistance of circuit by connecting 50 resistance of 1/4 Ω in parallel is---
50/4Ω
200Ω
4/50Ω
1/200Ω
4965. Three resistance 14.5Ω, 25.5Ω and 60Ω are connected in series across 200V. What will be the voltage drop across 14.5Ω?
29V
14V
13.5V
18V
4966. What happens if an electric bulb rated at 220V is connected to 220V, 5 Hz ac source? The bulb-
does not glow
fuses
glows continuously
glows intermittently
4967. Permeability in a magnetic circuit corresponds to--in electric circuit.
conductivity
conductance
resistivity
resistance
4968. A 50V battery is connected across 10Ω resistor. The current is 4.5 A. The internal resistance of the battery is-
zero
0.5Ω
5Ω
1.1Ω
4969. Kirchhoff's current law at a junction deals with-
Conversation of energy
Conversation of momentum
Conversation of charge
Conversation of angular momentum
4970. Kirchhoff's voltage law deals with—
Conversation of energy
Conversation of momentum
Conversation of charge
Conversation of angular momentum
4971. The resistance of each arm of Wheatstone bridge is 10 Ω. A resistance of 10Ω is connected in series with the galvanometer. The equivalent resistance across the battery will be-
40 Ω
20 Ω
30 Ω
10 Ω
4972. A wire has a resistance of 122. It is bent in the form of a circle. The effective resistance between the two points on any diameter of the circle is--
6Ω
12Ω
3Ω
24Ω
4973. Electrical appliances are connected in parallel because it-
Is a simple circuit
Draws less current
Results in reduced power loss
Makes the operation of appliances independent of each other
4974. Two resistors of 18Ω and 5Ω are connected in series to a 230 volt supply. The current is-
12A
10A
10.5A
9.5A
4975. The true statement for a series and a parallel de circuit is--
powers are additive
current are additive
element have individual current
voltage are additive
4976. What will be the internal resistance of cell, if it supplies 0.9A current through 2Ω resistor and 0.3A current through 7Ωresistor?
0.9Ω
1.2Ω
0.5Ω
1Ω
4977. The internal resistance of a cell of e.m.f 2V is 0.1Ω It is connected to a resistance of 3.9Ω. The voltage across the cell is-
0.5V
1.9V
1.95V
2V
4978. If a galvanometer is open circuited in a balanced Wheatstone bridge, the current in various resistors of Wheatstone bridge will---
Increase
Decrease
Not change
Cannot say anything
4979. An external resistance R is connected to a cell of internal resistance r. The maximum current flows in the external resistance when-
R<r
R=r
R>r
None of the above
4980. A 40W bulb is connected in parallel with room heater. What will happen if we turn off bulb?
Heater output will increase
Heater output will decrease
Heater output will remains same
None of the above