Key Topic 9: Ohm's Law-1

Question 0

3-9B1: What value series resistor would be needed to obtain a full-scale deflection on a 50 µA DC meter with an applied voltage of 200 V DC?

A. 4 megohms.
B. 2 megohms.
C. 400 kilohms.
D. 200 kilohms.

Answer 0

A. 4 megohms

Question 1

3-9B2: Which of the following Ohm’s law formulas is incorrect?

A. I = E / R
B. I = R / E
C. E = I x R
D. R = E / I

Answer 1

B. I = R / E

Question 2

3-9B3: If the current of two amperes flows through a 50-ohm resistor, what is the voltage across the resistor?

A. 25 volts.
B. 52 volts.
C. 200 volts.
D. 100 volts.

Answer 2

D. 100 volts.

Question 3

3-9B4: If a 100-ohm resistor is connected across 200 volts, what is the current through the resistor?

A. 2 amperes.
B. 1 ampere.
C. 300 amperes.
D. 20,000 amperes.

Answer 3

A. 2 amperes

Question 4

3-9B5: If a current of 3A flows through resistor connected to 90V, what is the resistance?

A. 3 ohms.
B. 30 ohms.
C. 93 ohms.
D. 270 ohms.

Answer 4

B. 30 ohms.

Question 5

3-9B6: A relay coil has 500 ohms resistance, and operates on 125 mA. What value of resistant should be connected in series with it to operate from 110 V DC?

A. 150 ohms.
B. 220 ohms.
C. 380 ohms.
D. 470 ohms.

Answer 5

C. 380 ohms.