WORD PROBLEM ELECTRICITY

Front

Maria sets up an electric circuit in her science class. She connects a battery, an ammeter, and a small lamp in series. Then she connects a voltmeter across the lamp. When she switches on the circuit, the ammeter shows a reading of 0.06 A, and the voltmeter shows that the lamp has a potential difference of 6 V across it.

a. What is the resistance of the lamp?

b. How much electrical power is the lamp using?

Back

A. Resistance = 100 Ω

B. Power = 0.36 W

Front

In a science experiment, a 6-volt battery is connected in a series with an ammeter, a resistor, and a lamp. The ammeter shows a current of 0.04 A, and the resistor connected in the circuit has a resistance of 100 Ω.

a. What is the voltage across the 100 Ω resistor

b. How much voltage left in the lamp?

Back

a. Voltage across the 100 Ω resistor : V = IR

Voltage across resistor = 4 V

b. Voltage across lamp = 6 − 4
Voltage across lamp = 2 V

Front

A small electric circuit in a science lab has a battery connected to a three separate branches. When the current leaves the battery, an ammeter measures a total current of 0.09 A. The current then reaches a junction where it splits into two branches. The right branch contains two bulbs, and an ammeter in this branch measures a current of 0.03 A. The middle branch contains one light bulb and another ammeter that measures the remaining current.

a. How much current flows through the middle branch?

Back

a. Current in the middle branch

Formula: Total current = sum of branch currents

Current in middle branch = 0.06 A

Front

A torch uses 6 V battery, and the current through the lamp is 300 mA

a. Calculate the power of the torch.

b. Calculate the resistance of the lamp.

Back

a. Power of the torch

Formula: P = VI

Power = 1.8 W

b. Resistance of the lamp

Formula: R = V ÷ I

Resistance = 20 Ω

Front

Resistor Color Code

Given:

Digits: Red = 2, Violet = 7
Multiplier: Orange = ×1,000
Tolerance: Silver = ±10%

a. Tolerance of the resistor

b. Minimum and Maximum Resistance

Back

a. Tolerance = ±10%

b. Minimum and Maximum Resistance

Minimum = 24,300 Ω

Maximum = 29,700 Ω