Chap 15 Practical Electricity (5105)

Draw

An LED bulb rated 240 V lights up a room for 30 minutes. Given that a current of 0.04 A flows through the bulb, calculate the energy transferred to the bulb. 

Multiple Choice

Which is correct?

• A

• B

• C

• D

Draw

A cooker has a power of 200 W when connected to a 240 V mains supply. Calculate

(a)the current in the cooker,

(b)the cost of using the cooker for 16 hours. The cost for 1.0 kWh of energy is 25 cents.

Open Ended

What is the most dangerous thing you have done with electricity?

Multiple Choice

What is the answer?

• A

• B

• C

• D

Multiple Choice

What is the answer?

• In the event of electrical fault, the earth wire will direct the current in the metal case to the ground and protect user from electric shock

• In the event of electrical fault, the earth wire will stop the current from flowing through the metal case and protects user from electric shock

• In the event of electrical fault, the earth wire will prevent the metal case from overheating by directing the current to the ground

• In the event of electrical fault, the earth wire will prevent the metal case from melting and damage the appliance