514

Physics Current Electricity Level: High School

When a 24.0 ohm resistor is connected across a 12.0 V battery , a currenof 482 mA flows . What is the resulting terminal voltage of the battery ?

a. 0.4 V

b. 5.8 V

c. 11.6 V

d. 12.0 V

509

Physics Current Electricity Level: High School

The temperature coefficient of resistivity for a “perfect” ohmic material would be .

a. positive and constant.

b. zero .

c. negative .

d. positive and uniformly increasing .

507

Physics Current Electricity Level: High School

A metal wire has a resistance of 25.00 ohm . Under room temperature conditions of 25 degreeC when the wire is heated to 85 degreeC the resistance increases by 0.75 ohm . What is the temperature coefficient of resistivity of this metal ?

a. 5.0 x 10-4(degreeC)-1

b. 1.3 x 10-3(degreeC)-1

c. 1.5 x 10-3(degreeC)-1

d. 2.5 x 10-3(degreeC)-1

503

Physics Current Electricity Level: High School

When an electric current exist s within a conducting wire , which of the following statement describes the condition of any accompanying electric field ?

a. must be zero .

b. must be parallel to current flow .

c. Must be anti-parallel (opposite direction) to current flow .

d. must be perpendicular to current flow .

502

Physics Current Electricity Level: High School

If a metallic wire of cross sectional area 3.0 x 10-6 m2 carries a current of 6.0 A and has a mobile charge density of 4.24 x 1028 carriers/m3 , What is the average drift velocity of the mobile charge carriers ? (charge value = 1.6 x 10-19 C)

a. 3.4 x 103 m/s

b. 1.7 x 103 m/s

c. 1.5 x 10-4 m/s

d. 2.9 x 10-4 m/s

495

Physics Current Electricity Level: High School

The circuit in the figure which is shown at ‘click here” is composed of two batteries ( E1=5V and E2=4V ) and three resistors (R1 = 3ohm, R2 = 3ohm, R3=4ohm) as shown.

a . What is the current I 3 flowing through the batteries ?

b . What is the voltage Vb-Va between the points a and b in the circuit ?

493

Physics Current Electricity Level: High School

The circuit in the figure which is shown at “click here” is composed of two batteries (V1=4V and V2 = 9V) and four resistors (R1 = 110 ohm, R2 = 40 ohm, R3 = 50 ohm, and R4 = 50 ohm ) as shown .

(a) What is the current which flows through R1 ?

(b) What is the current I 3 that flows through R3 ?

480

Physics Current Electricity Level: High School

Determine the power dissipated by each resistor in the attached circuit .

262

Physics Current Electricity Level: High School

Find the current through each resistor in the diagram as shown at "click here" .