What is the primary function of a step-up transformer?
A Increase current
B Increase voltage
C Decrease voltage
D Decrease current
A step-up transformer is designed to increase the voltage from the primary to the secondary winding. This is useful in power transmission systems, where high voltage is required to reduce energy loss over long distances.
What is the main advantage of using an autotransformer?
A Cost efficiency
B Higher efficiency
C Increased size
D Voltage regulation
Autotransformers are more cost-efficient than traditional transformers because they use fewer windings while still performing voltage conversion. The shared winding between primary and secondary reduces material costs, making them ideal for smaller applications.
In a step-down transformer, what happens to the voltage?
A It increases
B It fluctuates
C It stays the same
D It decreases
A step-down transformer reduces the voltage from the primary winding to the secondary winding. It’s commonly used in applications like power distribution, where high voltage is stepped down to a safer level for residential or commercial use.
Which of these is a common application of a step-down transformer?
A Voltage regulation
B Power generation
C Home appliances
D Power transmission
Step-down transformers are used in household applications to reduce the high transmission voltage to a lower, usable level for powering appliances, lighting, and other devices safely within homes or offices.
How does an autotransformer differ from a traditional transformer?
A Uses only one winding
B Lower efficiency
C Larger size
D Higher voltage rating
An autotransformer uses a single winding for both primary and secondary circuits, in contrast to traditional transformers, which use separate windings for each. This shared winding results in cost savings and smaller transformer size.
Which transformer is typically used for very high-voltage transmission lines?
A Isolation transformer
B Step-up transformer
C Step-down transformer
D Autotransformer
Step-up transformers are used in high-voltage transmission lines to increase voltage before transmission. Higher voltage reduces the current, which minimizes the energy loss over long distances, ensuring efficient power delivery.
What is one disadvantage of using an autotransformer compared to a conventional transformer?
A Larger size
B Lower efficiency
C No isolation
D High cost
Unlike conventional transformers, autotransformers do not provide electrical isolation between the primary and secondary windings. This can be a disadvantage in applications where isolation is necessary for safety or equipment protection.
In which situation is an autotransformer preferred over a traditional transformer?
A High power applications
B High isolation needs
C High voltage applications
D Cost-sensitive applications
Autotransformers are preferred in cost-sensitive applications because they use fewer materials than traditional transformers, making them more affordable. They are commonly used in situations requiring moderate voltage conversion with efficiency.
What type of transformer is used to connect different voltage systems?
A Isolation transformer
B Power transformer
C Step-down transformer
D Step-up transformer
Isolation transformers are used to connect different voltage systems, providing electrical isolation between the circuits. This helps in protecting equipment from electrical surges and grounding issues, and is used in sensitive systems like medical equipment.
What occurs when the turns ratio of a transformer is 1:1?
A Voltage increases
B Voltage remains the same
C Current increases
D Voltage decreases
When the turns ratio of a transformer is 1:1, there is no change in the voltage. The primary and secondary windings have equal numbers of turns, meaning the voltage remains the same in both windings, useful in isolation applications.
What is a primary advantage of using a step-up transformer in power generation?
A Increase current
B Decrease voltage
C Reduce energy loss
D Increase efficiency
Step-up transformers increase the voltage for power transmission, which reduces the current. Lower current reduces the resistive losses in transmission lines, thereby minimizing energy loss and improving the efficiency of long-distance power distribution.
What is the main disadvantage of a step-down transformer?
A Increased current
B Increased cost
C Larger size
D Higher voltage
A step-down transformer decreases voltage but increases the current in the secondary winding. This increase in current can result in higher energy losses in the form of heat in cables and other components in the electrical system.
How does the number of turns in the secondary winding of a step-down transformer compare to the primary?
A Equal
B More
C None
D Fewer
In a step-down transformer, the secondary winding has fewer turns than the primary winding. This reduces the voltage in the secondary circuit, which is ideal for applications requiring lower voltage, such as household appliances.
Which type of transformer is used to safely connect two circuits with different voltage levels without direct electrical connection?
A Power transformer
B Autotransformer
C Isolation transformer
D Step-up transformer
An isolation transformer is used to safely connect two circuits with different voltage levels while providing electrical isolation between them. This is crucial for protecting sensitive equipment and preventing electrical faults from propagating.
What is the key advantage of using a step-up transformer in electrical distribution?
A Increase efficiency
B Increase voltage
C Reduce energy consumption
D Decrease size
Step-up transformers are used in electrical distribution systems to increase the voltage for efficient long-distance transmission. This allows the transmission of power at a higher voltage, reducing losses and improving the system’s overall efficiency.