Physics

7 years ago

A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. ...

A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. When this system reaches its steady-state, the voltage across the resistor is
A) greater than the battery's terminal voltage.
B) equal

Brelou 100 1 Reply

7 years ago

A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. ...

A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage across the resistor is
A) greater than the battery's terminal voltage.
B)

Brelou 108 1 Reply

7 years ago

A pure capacitor is connected to an AC power supply. In this circuit, the current

A pure capacitor is connected to an AC power supply. In this circuit, the current
A) leads the voltage by 90°.
B) lags the voltage by 90°.
C) lags the voltage by 180°.
D) is in phase with the voltage.
E) none of the giv

Brelou 83 1 Reply

7 years ago

Consider a capacitor connected across the AC supply. The current through the capacitor will ________ ...

Consider a capacitor connected across the AC supply. The current through the capacitor will ________ as the capacitance is increased.
A) increase
B) remain constant
C) decrease

tankster 92 1 Reply

7 years ago

If you triple the rms voltage in an ac circuit, what happens to the maximum voltage?

If you triple the rms voltage in an ac circuit, what happens to the maximum voltage?
A) It increases by a factor of .
B) It decreases by a factor of .
C) It decreases by a factor of 3.
D) It increases by a factor

Brelou 117 1 Reply

7 years ago

An electric circuit consists of a resistor connected across the terminals of an ac generator. How ...

An electric circuit consists of a resistor connected across the terminals of an ac generator. How does the power dissipated in the resistor change as the frequency in the generator decreases?
A) It decreases.
B) It increases.
C) It doe

tankster 99 1 Reply

7 years ago

A resistor is connected to an AC power supply. On this circuit, the current

A resistor is connected to an AC power supply. On this circuit, the current
A) leads the voltage by 90°.
B) lags the voltage by 90°.
C) is in phase with the voltage.
D) leads the voltage by 45°.
E) lags the voltage by 45°.

Brelou 91 1 Reply

7 years ago

A series RLC circuit connected across an ac voltage source will have a positive value of the phase ...

A series RLC circuit connected across an ac voltage source will have a positive value of the phase angle at high frequencies.

tankster 122 1 Reply

7 years ago

In a series RLC circuit an inductor will be dominant at higher frequencies.

tankster 75 1 Reply

7 years ago

The inductive reactance of an inductor is higher at low frequencies.

tankster 91 1 Reply

7 years ago

The capacitive reactance of a capacitor is very small at low frequencies.

Northa 95 1 Reply

7 years ago

The capacitive reactance increases with the capacitance.

tankster 84 1 Reply

7 years ago

The capacitive reactance is directly proportional to the frequency of the applied ac signal.

Northa 115 1 Reply

7 years ago

An ac signal of a certain frequency is applied to a capacitor. The current leads the voltage by ...

An ac signal of a certain frequency is applied to a capacitor. The current leads the voltage by 90°.

Brelou 109 1 Reply

7 years ago

The primary coil of a transformer has 600 turns and its secondary coil has 150 turns. If the ac ...

The primary coil of a transformer has 600 turns and its secondary coil has 150 turns. If the ac current in the primary coil is 2 A, what is the current in its secondary coil?
A) 8 A
B) 1/2 A
C) 1/4 A
D) 2 A
E) 4 A

tankster 129 1 Reply

7 years ago

The primary coil of a transformer has 100 turns and its secondary coil has 400 turns. If the ac ...

The primary coil of a transformer has 100 turns and its secondary coil has 400 turns. If the ac current in the secondary coil is 2 A, what is the current in its primary coil?
A) 2 A
B) 8 A
C) 1/2 A
D) 1/4 A
E) 4 A

Brelou 128 1 Reply

7 years ago

A step-up transformer doubles a primary voltage 110 V (ac). What is the ratio of the number of turns ...

A step-up transformer doubles a primary voltage 110 V (ac). What is the ratio of the number of turns in its primary coil to those in the secondary coil?
A) 1:4
B) 4:1
C) 2:1
D) 1:2
E) 1:8

tankster 210 1 Reply

7 years ago

The primary coil of a transformer has 100 turns and its secondary coil has 400 turns. If the ac ...

The primary coil of a transformer has 100 turns and its secondary coil has 400 turns. If the ac voltage applied to the primary coil is 120 V, what voltage is present in its secondary coil?
A) 100 V
B) 30 V
C) 70 V
D) 480 V

tankster 131 1 Reply

7 years ago

A 1.5-H inductor is connected in series with a 200-Ω resistor through a 15-V dc power supply and a ...

A 1.5-H inductor is connected in series with a 200-Ω resistor through a 15-V dc power supply and a switch. If the switch is closed at t = 0 s, what is the maximum energy stored by the inductor?
A) 1.2 mJ
B) 2.2 mJ
C) 3.2 mJ
D) 4.2

tankster 193 1 Reply

7 years ago

In an RL series circuit connected to a dc source and a switch, the inductor gets 40% of its maximum ...

In an RL series circuit connected to a dc source and a switch, the inductor gets 40% of its maximum current 1.8 s after the switch is closed at t = 0 s. What is the time constant of this circuit?
A) 0.80 s
B) 1.5 s
C) 2.5 s
D) 3.5

Brelou 473 1 Reply

7 years ago

A 25-mH inductor is connected in series with a 20-Ω resistor through a 15-V dc power supply and a ...

A 25-mH inductor is connected in series with a 20-Ω resistor through a 15-V dc power supply and a switch. If the switch is closed at t = 0 s, what is the current when t = 2.0 ms?
A) 0.40 A
B) 0.50 A
C) 0.60 A
D) 0.70 A
E) 0.8

tankster 124 1 Reply

7 years ago

A 25.0-mH inductor is connected in series to a 20.0-Ω resistor through a 15.0-V dc power supply and ...

A 25.0-mH inductor is connected in series to a 20.0-Ω resistor through a 15.0-V dc power supply and a switch. If the switch is closed at t = 0 s, what is the time constant of this circuit?
A) 0.800 × 10-3 s
B) 0.800 × 10-2 s
C) 0.500 s

Brelou 143 1 Reply

7 years ago

The inductance of a solenoid 16.0 cm long with a cross-sectional area of 1.00 × 10-4 m2 is 1.00 mH. ...

The inductance of a solenoid 16.0 cm long with a cross-sectional area of 1.00 × 10-4 m2 is 1.00 mH. How many turns of wire does this solenoid have?
A) 318,000
B) 159,000
C) 1130
D) 282
E) 150

Northa 265 1 Reply

7 years ago

A coil with a self-inductance of 6.0 H is connected to a dc source through a switch. As soon as the ...

A coil with a self-inductance of 6.0 H is connected to a dc source through a switch. As soon as the switch is closed at t = 0 s, the rate of change of current is 2.0 A/s. What is the emf induced in this coil at t = 0 s?
A) 6.0 V
B) 3.0 V

tankster 105 1 Reply

7 years ago

A coil with a self-inductance of 6 H has a constant current of 2 A flowing through it for 2 seconds. ...

A coil with a self-inductance of 6 H has a constant current of 2 A flowing through it for 2 seconds. What is the emf induced in this coil?
A) 6 V
B) 12 V
C) 0 V
D) 4 V
E) 8 V

Northa 144 1 Reply

7 years ago

A constant magnetic field is applied perpendicular to the plane of a square, single-turn coil with ...

A constant magnetic field is applied perpendicular to the plane of a square, single-turn coil with each side equal to 15 cm. If the area of the coil decreases at a rate of 0.20 m2/s, an emf of 20 mV is induced in that coil. What is the strength of th

tankster 163 1 Reply

7 years ago

A uniform magnetic field is applied perpendicular to the plane of a 60-turn circular coil with a ...

A uniform magnetic field is applied perpendicular to the plane of a 60-turn circular coil with a radius of 6.0 cm and a resistance of 0.60 Ω. If the magnetic field increases from 0.20 T to 1.8 T in 0.20 s, what is the emf induced in that coil?
A

Northa 130 1 Reply

7 years ago

A single-turn plane loop of wire with a cross-sectional area 200 cm2 is perpendicular to a magnetic ...

A single-turn plane loop of wire with a cross-sectional area 200 cm2 is perpendicular to a magnetic field that increases uniformly from 0.200 T to 2.800 T in 2.20 seconds. What is the magnitude of the induced current if the resistance of the coil is

tankster 149 1 Reply

7 years ago

A conducting loop of wire has an area of 150 cm2 and a resistance of 25.0 Ω. There is a magnetic ...

A conducting loop of wire has an area of 150 cm2 and a resistance of 25.0 Ω. There is a magnetic field of 100 T perpendicular to the loop. At what rate must this field be reduced to induce a current of 0.100 A in the loop?
A) 167 T/s
B) 60.

Brelou 84 1 Reply

7 years ago

A constant magnetic field of 0.50 T is applied to a rectangular loop of area 3.0 × 10-3 m2. If the ...

A constant magnetic field of 0.50 T is applied to a rectangular loop of area 3.0 × 10-3 m2. If the area of this loop changes from its original value to a new value of 1.6 × 10-3 m2 in 1.6 s, what is the emf induced in the loop?
A) 1.6 × 10-2 V

Northa 127 1 Reply

7 years ago

The area of a rectangular loop of wire is 3.6 × 10-3 m2. The loop is placed in a magnetic field ...

The area of a rectangular loop of wire is 3.6 × 10-3 m2. The loop is placed in a magnetic field that changes from 0.20 T to 1.4 T in 1.6 s. The plane of the loop is perpendicular to the direction of the magnetic field. What is the magnitude of the in

tankster 192 1 Reply

7 years ago

A conducting loop in the form of a circle is placed perpendicular to a magnetic field of 0.50 T. If ...

A conducting loop in the form of a circle is placed perpendicular to a magnetic field of 0.50 T. If the area of the loop increases at a rate of 3.0 × 10-3 m2/s, what is the induced emf in the loop?
A) 4.3 mV
B) 0 mV
C) 1.5 mV
D) 1

Brelou 151 1 Reply

7 years ago

A power transmission line 50. km long has a total resistance of 0.60 Ω. A generator produces 100. V ...

A power transmission line 50. km long has a total resistance of 0.60 Ω. A generator produces 100. V at 70. A. In order to reduce energy loss due to heating of the transmission line, the voltage is stepped up with a transformer with a turns ratio of 1

Brelou 223 1 Reply

7 years ago

A transformer has a turns ratio of 10. The primary voltage and current are 120. volts and 20. ...

A transformer has a turns ratio of 10. The primary voltage and current are 120. volts and 20. Amperes.
(a) What is the primary impedance (ratio of primary voltage to current)?
(b) What is the secondary impedance?

Northa 105 1 Reply

7 years ago

A 90.% efficient transformer supplies 3.0 Amperes at 6.0 volts. If the input voltage is 120. v, what ...

A 90.% efficient transformer supplies 3.0 Amperes at 6.0 volts. If the input voltage is 120. v, what is the input current?

Brelou 110 1 Reply

7 years ago

An ideal transformer has 60. turns on its primary coil and 300. turns on its secondary coil. If 120. ...

An ideal transformer has 60. turns on its primary coil and 300. turns on its secondary coil. If 120. V at 2.0 A is applied to the primary, what voltage and current are present in the secondary?

Brelou 123 1 Reply

7 years ago

A transformer with 120. turns in its secondary supplies 12. volts at 220. ma to a toy train. The ...

A transformer with 120. turns in its secondary supplies 12. volts at 220. ma to a toy train. The primary is connected across a 120. V wall outlet.
(a)   How many turns are in the primary?
(b)   What is the primary current?
(c)   What power i

tankster 177 1 Reply

7 years ago

A step-down transformer is needed to reduce a primary voltage of 120. V AC to6.0 V AC. What turns ...

A step-down transformer is needed to reduce a primary voltage of 120. V AC to
6.0 V AC. What turns ratio is required?

tankster 146 1 Reply

7 years ago

The starting current in a DC motor is 20. A, but it normally operates on 110. volts with a back EMF ...

The starting current in a DC motor is 20. A, but it normally operates on 110. volts with a back EMF of 90. volts.
(a) What is the resistance in the windings?
(b) What is the current at normal load?

Northa 80 1 Reply