Transformer Functions and Calculations

This video tutorial covers the concept of electromagnetic induction, focusing on transformers. It explains the difference between ideal and non-ideal transformers, including their efficiency and power loss. The tutorial provides detailed calculations and example problems to illustrate these concepts, helping students understand how transformers work in real-world applications.

What is the primary function of a transformer in daily life?

• To change voltage levels

• To generate electricity

• To convert electrical energy into mechanical energy

• To store electrical energy

In an ideal transformer, what is the efficiency percentage?

• 50%

• 75%

• 100%

• 90%

What happens to the current when the voltage is increased in a step-up transformer?

• The current increases

• The current decreases

• The current remains the same

• The current becomes zero

In a transformer problem, if the primary voltage is 200V and the efficiency is 60%, what is the secondary voltage if the primary current is 0.05A and the secondary current is 0.4A?

• 50V

• 15V

• 30V

• 100V

How do you calculate the power on the secondary coil of a transformer?

• Voltage divided by current

• Voltage times resistance

• Voltage times current

• Current divided by resistance

If a step-up transformer increases voltage from 50V to 250V, what is the primary current if the secondary power is 60W and efficiency is 60%?

• 4A

• 2A

• 1A

• 3A

What is the relationship between the number of turns in the primary and secondary coils and the voltage in a transformer?

• Directly proportional

• Inversely proportional

• No relationship

• Exponentially proportional

In a transformer, if the primary coil has 200 turns and the secondary coil has 1000 turns, what is the voltage ratio?

• 1:2

• 1:5

• 2:1

• 5:1

What is the power loss in a transformer if the input power is 100W and the output power is 80W?

• 40W

• 30W

• 20W

• 10W

If a device is rated at 250V and 500W, but connected to a 200V supply, what is the adjusted power consumption?

• 400W

• 320W

• 600W

• 500W