How Two Boys Made Their Own Electrical Apparatus Trivia Quiz Questions and Answers

You’re in your workshop, trying to build a telegraph system using an 1898 guidebook. Which of these materials will you need to make a simple battery for your system?

Glass
Rubber
Copper wire
Vinegar

Correct Answer: Vinegar

Correct Answer Explanation: Vinegar can be used as an electrolyte in a simple battery, along with zinc and carbon electrodes. This setup, though not very powerful, is a basic example of a wet cell battery.

What is the main reason you would use a bichromate solution in a battery, as described in the 1898 guidebook?

To make the battery stronger
To prevent corrosion
To make the battery last longer
To add a special color to the battery

Correct Answer: To make the battery stronger

Correct Answer Explanation: Bichromate solutions are strong electrolytes, meaning they conduct electricity well and allow for a more powerful battery. It was commonly used in batteries built in the late 19th century.

What is the best way to prevent corrosion on zinc plates in a battery, as recommended in “How Two Boys Made Their Own Electrical Apparatus?”

Soak them in vinegar for 24 hours.
Paint them with a layer of varnish.
Use mercury to amalgamate the zinc.
Wrap them in a layer of rubber.

Correct Answer: Use mercury to amalgamate the zinc.

Correct Answer Explanation: Amalgamation, the process of coating zinc with mercury, was a common practice in the 1800s to prevent corrosion. The mercury forms a protective layer on the zinc, slowing down its reaction with the battery fluid.

You’re constructing a telegraph key for your system. Why are two binding posts necessary for the key to function properly, according to the instructions in the book?

To hold the key securely in place.
To connect the battery to the wire.
To connect the wire to the sounder.
To allow for a closed circuit when the key is pressed.

Correct Answer: To allow for a closed circuit when the key is pressed.

Correct Answer Explanation: In a telegraph system, the key acts as a switch, breaking and closing the circuit to transmit signals. Two binding posts allow for a complete circuit when the key is pressed and a broken circuit when it’s released.

You’re building a simple electromagnet using a soft iron core and copper wire. What’s the best way to increase the strength of the electromagnet, based on the information from the 1898 book?

Increase the length of the wire.
Reduce the thickness of the wire.
Increase the number of turns of wire around the core.
Use a thicker iron core.

Correct Answer: Increase the number of turns of wire around the core.

Correct Answer Explanation: According to the guidebook, increasing the number of turns of wire around the core increases the strength of the magnetic field produced by the electromagnet. This principle is still used in modern electromagnets.

Your guidebook instructs you to use sheet tin, a type of soft iron, for specific parts of your electrical devices. Why is soft iron preferred over steel for electromagnets?

Soft iron is cheaper than steel.
Soft iron is more resistant to corrosion.
Soft iron is easier to magnetize and demagnetize.
Soft iron is stronger than steel.

Correct Answer: Soft iron is easier to magnetize and demagnetize.

Correct Answer Explanation: Soft iron readily gains and loses its magnetic properties, making it ideal for cores in electromagnets. Steel, on the other hand, retains its magnetic properties more persistently, which is less useful in this application.

You’re interested in making a current detector using a magnetic needle. How can you make this detector more sensitive, based on the information from the 1898 guidebook?

Use a stronger battery.
Use a thicker copper wire.
Use a longer magnetic needle.
Use an astatic needle.

Correct Answer: Use an astatic needle.

Correct Answer Explanation: An astatic needle is a pair of magnetic needles, arranged so their poles are opposite. This arrangement makes the needle less influenced by the Earth’s magnetic field, making it more sensitive to weaker currents.

In the late 1800s, what did electrical engineers consider a suitable material for creating a high-resistance component in a circuit?

Copper
Aluminum
German silver
Iron

Correct Answer: German silver

Correct Answer Explanation: German silver, an alloy of copper, nickel, and zinc, was known for its high electrical resistance, making it useful in components like rheostats and resistors.

While building your own electric motor, you need to ensure the current flow through the armature reverses each time it rotates half a revolution. What device is used for this purpose in a simple electric motor, as described in the 1898 guidebook?

Electromagnet
Armature
Commutator
Binding posts

Correct Answer: Commutator

Correct Answer Explanation: A commutator, a split ring connected to the armature, is essential in simple electric motors. It reverses the direction of current flow in the armature every half turn, ensuring continuous rotation.

In the 1898 book, what is described as a simple but effective method for producing a shock from an induction coil?

Connecting the coil to a strong battery
Using a rapidly interrupting current
Using a high-voltage transformer
Wrapping the coil in insulating material

Correct Answer: Using a rapidly interrupting current

Correct Answer Explanation: The guidebook describes how rapidly interrupting the current in the primary coil of an induction coil creates a sudden surge of voltage in the secondary coil, leading to a shock. This was a common way to demonstrate induction in the late 19th century.

You’re building a small electric bell for your home. What is the main function of the armature in this device, as explained in the guidebook?

To produce a ringing sound
To connect the electromagnet to the bell
To attract the hammer to the bell
To provide insulation for the circuit

Correct Answer: To attract the hammer to the bell

Correct Answer Explanation: The armature is a piece of soft iron connected to the hammer. When the electromagnet is energized, it attracts the armature, causing the hammer to strike the bell. This creates the ringing sound.

You are learning about different types of batteries in your 1898 guidebook. Which of these types of batteries is designed to provide a consistent current for a long period of time?

Carbon-zinc battery
Gravity battery
Induction coil battery
Smee battery

Correct Answer: Gravity battery

Correct Answer Explanation: The gravity battery, a type of wet cell battery with copper sulfate solution and zinc plates, was known for its long-lasting current output and was commonly used in telegraph systems during the 19th century.

In the 1898 guidebook, what is the primary use for the induction coil in an electrical system?

To create a more powerful battery.
To produce sparks for lighting.
To send Morse code signals
To increase the voltage of a current.

Correct Answer: To increase the voltage of a current.

Correct Answer Explanation: An induction coil uses electromagnetic induction to increase the voltage of a current. This principle was crucial in the early development of electrical technology, and induction coils were used for various applications, including shock generation and wireless telegraphy.

You are trying to send a message to a friend using a telegraph system you built. Which of these is a valid Morse code character?

.-
.-..-.–
-..—

Correct Answer: .-

Correct Answer Explanation: The Morse code character for the letter “A” is “.-“. This simple code, consisting of dots and dashes, was instrumental in long-distance communication before the advent of modern telecommunications.

How many feet of No. 20 annunciator wire would weigh approximately 1 pound, according to your guidebook?

Correct Answer: 235

Correct Answer Explanation: The guidebook states that 235 feet of No. 20 annunciator wire weighs about 1 pound. This kind of information was useful for electricians in the late 19th century when they needed to calculate the weight of wire for different projects.

You’ve built a basic electric motor using an electromagnet and an armature. What is the main function of the brushes in this motor?

To ensure the armature stays in place
To transfer current from the battery to the armature
To prevent the motor from overheating
To increase the strength of the electromagnet

Correct Answer: To transfer current from the battery to the armature

Correct Answer Explanation: The brushes are conductive components that make contact with the commutator, transferring current from the battery to the armature. This continuous flow of current through the armature creates the magnetic field that rotates the motor.

What is the primary difference between an electromagnet and a permanent magnet, as explained in the 1898 guidebook?

An electromagnet is made of steel, while a permanent magnet is made of iron.
An electromagnet is stronger than a permanent magnet.
An electromagnet’s magnetism can be turned on and off, while a permanent magnet’s magnetism is always present.
An electromagnet is used in motors, while a permanent magnet is used in compasses.

Correct Answer: An electromagnet’s magnetism can be turned on and off, while a permanent magnet’s magnetism is always present.

Correct Answer Explanation: The book emphasizes that electromagnets, unlike permanent magnets, can be controlled. Turning the current on and off in the coil creates and eliminates the magnetic field. This controllability makes electromagnets crucial for various applications like motors, relays, and solenoids.

You’re learning about the principles of electromagnetism from the guidebook. What happens when an electric current flows through a wire, as described in the book?

The wire becomes heated.
The wire produces a magnetic field.
The wire attracts other wires.
The wire emits light.

Correct Answer: The wire produces a magnetic field.

Correct Answer Explanation: The book explains that a magnetic field surrounds any wire carrying an electric current. This discovery, known as Oersted’s Law, was fundamental to the development of electromagnetism and the understanding of the relationship between electricity and magnetism.

You’re building an electric motor for your model train. Why is it necessary to use soft iron for the armature of the motor?

Soft iron is a good conductor of electricity.
Soft iron is cheap and readily available.
Soft iron is easily magnetized and demagnetized.
Soft iron is strong and durable.

Correct Answer: Soft iron is easily magnetized and demagnetized.

Correct Answer Explanation: The guidebook highlights the importance of using soft iron for the armature because it readily gains and loses its magnetic properties. This allows the armature to be magnetized by the field magnets and then demagnetized as it rotates, ensuring smooth operation of the motor.

What type of battery is described in the book as being ideal for long-duration telegraph systems?

Carbon-zinc battery
Gravity battery
Induction coil battery
Smee battery

Correct Answer: Gravity battery

Correct Answer Explanation: The gravity battery was commonly used in telegraph systems because its design allowed for a consistent current flow over extended periods. The separation of the liquids by gravity prevented the mixing of solutions, ensuring a longer operational time.

What is the purpose of a commutator in an electric motor?

To reverse the current flow in the armature
To prevent the motor from overheating
To generate a strong magnetic field
To increase the speed of the motor

Correct Answer: To reverse the current flow in the armature

Correct Answer Explanation: The commutator, a split ring connected to the armature, is vital for the continuous rotation of a motor. It reverses the direction of current flow in the armature every half turn, ensuring that the armature continues to rotate in the same direction.

You are building a simple telegraph sounder for your system. What is the main function of the armature in the sounder?

To send Morse code signals
To connect the battery to the wire
To attract the hammer to the sounder
To produce a sound when struck

Correct Answer: To attract the hammer to the sounder

Your guidebook advises against using steel for certain parts of your electrical devices. What is the main reason for this?

Steel is expensive.
Steel is too heavy for most applications.
Steel is a poor conductor of electricity.
Steel retains its magnetism more strongly than soft iron.

Correct Answer: Steel retains its magnetism more strongly than soft iron.

Correct Answer Explanation: Steel, unlike soft iron, retains its magnetic properties more persistently. This is undesirable in applications where the magnetic field needs to be easily controlled, such as in electromagnets used in motors and sounders.

You are building a current detector using a magnetic needle. What happens to the needle when an electric current flows through a wire near it?

The needle deflects from its original position.
The needle becomes magnetized.
The needle spins rapidly.
The needle remains stationary.

Correct Answer: The needle deflects from its original position.

Correct Answer Explanation: When an electric current flows through a wire, it creates a magnetic field around the wire. This magnetic field interacts with the magnetic needle, causing it to deflect from its original north-south alignment. This deflection indicates the presence and direction of the current.

You’re building an induction coil to experiment with high-voltage electricity. Which of these is a primary component of the induction coil, as explained in the 1898 guidebook?

A permanent magnet
A battery
A commutator
A secondary coil

Correct Answer: A secondary coil

Correct Answer Explanation: The induction coil uses two coils, the primary and secondary coils. The secondary coil is the one that produces the high voltage, while the primary coil, energized by a battery, induces the current in the secondary coil.

What is the main principle behind the operation of a telegraph system, as explained in your guidebook?

The use of a static charge
The transmission of light signals
The use of a closed-circuit battery
The use of electromagnets to attract a hammer

Correct Answer: The use of a closed-circuit battery

Correct Answer Explanation: A telegraph system relies on a closed circuit, where the flow of current through a wire is controlled by a key. When the key is pressed, the circuit is closed, allowing current to flow and activate the sounder at the receiving end. When the key is released, the circuit is broken, stopping the sounder.

You are constructing a simple electric bell using an electromagnet. What is the primary function of the bell’s hammer in this system?

To complete the electrical circuit
To strike the bell to produce a sound
To attract the armature
To regulate the flow of current

Correct Answer: To strike the bell to produce a sound

Correct Answer Explanation: The hammer, attached to the armature, is the component that actually strikes the bell to create the ringing sound. When the electromagnet is energized, it pulls the armature, causing the hammer to hit the bell.

In the context of your 1898 guidebook, what does “amalgamation” refer to?

The process of connecting two wires
The process of coating zinc with mercury to prevent corrosion
The process of using a battery to generate electricity
The process of magnetizing a piece of iron

Correct Answer: The process of coating zinc with mercury to prevent corrosion

Correct Answer Explanation: Amalgamation, the process of coating zinc with mercury, was a common practice in the 19th century to prevent corrosion of zinc plates in batteries. The mercury forms a protective layer on the zinc, slowing down its reaction with the battery fluid.

What is a typical method for interrupting the current in an induction coil, as described in the guidebook?

Using a switch
Using a rotating armature
Using a vibrating armature
Using a capacitor

Correct Answer: Using a vibrating armature

Correct Answer Explanation: The guidebook describes how a vibrating armature, connected to the primary circuit, can be used to interrupt the current flow rapidly. This rapid interruption is what creates the high-voltage surge in the secondary coil, often resulting in a shock.

You are learning about the different types of magnets from your guidebook. Which type of magnet is created by passing an electric current through a coil of wire wrapped around a soft iron core?

Permanent magnet
Electromagnet
Static magnet
Magnetic needle

Correct Answer: Electromagnet

Correct Answer Explanation: An electromagnet is a temporary magnet created by passing an electric current through a coil of wire wrapped around a soft iron core. The magnetic field of an electromagnet exists only when the current is flowing, unlike a permanent magnet, which always has a magnetic field.

In the 1898 guidebook, why is German silver mentioned as a suitable material for high-resistance components in electrical circuits?

It is a good conductor of electricity
It is readily available and inexpensive
It has a high melting point
It has a high electrical resistance

Correct Answer: It has a high electrical resistance

Correct Answer Explanation: German silver, an alloy of copper, nickel, and zinc, is known for its high electrical resistance. This property makes it useful in resistors and rheostats, where controlling the flow of current is essential.

What is the main difference between a telegraph key and a telegraph sounder?

The key sends signals, while the sounder receives signals
The key uses a battery, while the sounder uses a magnet
The key is a switch, while the sounder is a receiver
The key is used for long-distance communication, while the sounder is used for short-distance communication

Correct Answer: The key is a switch, while the sounder is a receiver

Correct Answer Explanation: The telegraph key acts as a switch, opening and closing the circuit to send signals. The telegraph sounder receives these signals, producing a click sound for each dot or dash, which translates to Morse code.

You are building a simple electric motor for a small toy car. What is the primary function of the brushes in this motor?

To prevent the motor from overheating
To generate the magnetic field
To transfer current to the armature
To control the speed of the motor

Correct Answer: To transfer current to the armature

Why is soft iron preferred over steel for the core of an electromagnet, as explained in the guidebook?

Soft iron is easier to magnetize and demagnetize
Soft iron is cheaper than steel
Soft iron is stronger than steel
Soft iron is a better conductor of electricity

Correct Answer: Soft iron is easier to magnetize and demagnetize

Correct Answer Explanation: Soft iron, unlike steel, readily gains and loses its magnetic properties. This makes it ideal for electromagnets, where the magnetic field needs to be easily controlled by turning the current on and off. Steel retains its magnetism more strongly, making it less suitable for applications requiring controllable magnetism.

You’re building a simple telegraph key using a lever and two binding posts. Why are two binding posts necessary for the key to function properly?

To connect the key to the battery
To connect the key to the wire
To hold the key in place
To allow for a closed circuit when the key is pressed

Correct Answer: To allow for a closed circuit when the key is pressed

You’re trying to build a simple current detector using a magnetic needle and a coil of wire. What is the main reason you would use an astatic needle instead of a single magnetic needle?

An astatic needle is more sensitive to weak currents
An astatic needle is easier to build
An astatic needle is less expensive
An astatic needle produces a stronger magnetic field

Correct Answer: An astatic needle is more sensitive to weak currents

Correct Answer Explanation: An astatic needle consists of two magnetic needles, arranged so their poles are opposite. This arrangement reduces the influence of the Earth’s magnetic field, making the needle more sensitive to weaker currents.

What is the primary function of the electromagnet in an electric bell?

To provide insulation for the circuit
To attract the hammer to the bell
To produce a ringing sound
To regulate the flow of current

Correct Answer: To attract the hammer to the bell

Correct Answer Explanation: The electromagnet is the component that attracts the armature, which is connected to the hammer. When the electromagnet is energized, it pulls the armature, causing the hammer to strike the bell and produce a ringing sound.

You’re learning about the different types of batteries in your 1898 guidebook. Which type of battery is best known for its long-lasting current output, making it suitable for telegraph systems?

Carbon-zinc battery
Gravity battery
Smee battery
Induction coil battery

Correct Answer: Gravity battery

Correct Answer Explanation: The gravity battery, with its two-fluid design, was known for providing a steady current for extended periods. This made it a popular choice for telegraph systems, which required a continuous flow of electricity to transmit signals over long distances.

Which of these is a valid Morse code character?

–..
.-.-
…—
…-

Correct Answer: …-

Correct Answer Explanation: The Morse code character for the letter “S” is “…-“. This simple code, consisting of dots and dashes, was crucial in long-distance communication before the advent of modern telecommunications.

In the context of your 1898 guidebook, what is amalgamation?

The process of magnetizing a piece of iron
The process of connecting two wires
The process of using a battery to generate electricity
The process of coating zinc with mercury to prevent corrosion

Correct Answer: The process of coating zinc with mercury to prevent corrosion

You are building an induction coil to experiment with high-voltage electricity. What is the main purpose of the secondary coil in this device?

To interrupt the current flow
To store electrical energy
To produce high voltage electricity
To regulate the current flow

Correct Answer: To produce high voltage electricity

In the 1898 guidebook, what is the primary use for the induction coil in an electrical system?

To create a more powerful battery
To increase the voltage of a current
To send Morse code signals
To produce sparks for lighting

Correct Answer: To increase the voltage of a current

Why is it important to use an insulating material like rubber or glass when working with high-voltage electricity?

To prevent electrical shock
To increase the current flow
To regulate the voltage
To make the circuit more efficient

Correct Answer: To prevent electrical shock

Correct Answer Explanation: Insulating materials, like rubber or glass, do not conduct electricity well. They are used to prevent electrical shock by preventing the flow of current to the user’s body. This is crucial when working with high voltages as it can be dangerous.

You are building a simple electric motor using an electromagnet and an armature. What is the primary function of the armature in this motor?

To provide a path for the current
To generate a magnetic field
To control the speed of the motor
To connect the brushes to the battery

Correct Answer: To generate a magnetic field

Correct Answer Explanation: The armature is a rotating part of the motor that is magnetized by the field magnets. The magnetic field created by the armature interacts with the magnetic field of the field magnets, causing the armature to rotate.

You are learning about the principles of electromagnetism from the guidebook. What happens when an electric current flows through a wire?

The wire becomes heated.
The wire produces a magnetic field.
The wire attracts other wires.
The wire emits light.

Correct Answer: The wire produces a magnetic field.

Why is it important to use soft iron for the armature of a motor, as explained in the 1898 guidebook?

Soft iron is a good conductor of electricity.
Soft iron is cheap and readily available.
Soft iron is easily magnetized and demagnetized.
Soft iron is strong and durable.

Correct Answer: Soft iron is easily magnetized and demagnetized.

What is a gravity battery?

A battery that is designed to be used in a vertical position
A battery that is designed to be used in a horizontal position
A battery that is designed to be used in a horizontal position
A battery that is designed to be used in a horizontal position

Correct Answer: A battery that is designed to be used in a vertical position

Correct Answer Explanation: The gravity battery, a type of wet cell battery, is specifically designed to be used in a vertical position. The denser electrolyte solution, usually copper sulfate, settles at the bottom, creating a separation between the copper and zinc plates. This design allows for a more consistent current flow and longer operation time.

What is the primary function of the commutator in an electric motor?

To generate a strong magnetic field
To prevent the motor from overheating
To reverse the current flow in the armature
To control the speed of the motor

Correct Answer: To reverse the current flow in the armature

What is the primary function of the hammer in a telegraph sounder?

To connect the battery to the wire
To send Morse code signals
To produce a sound when struck
To attract the armature

Correct Answer: To produce a sound when struck

Correct Answer Explanation: The hammer, attached to the armature, is the component that actually strikes the sounder to create the “click” sound. When the electromagnet is energized, it pulls the armature, causing the hammer to hit the sounder.

What is the main reason you would use soft iron instead of steel for certain parts of your electrical devices, according to the 1898 guidebook?

Soft iron is cheaper than steel.
Soft iron is easier to magnetize and demagnetize.
Soft iron is stronger than steel.
Soft iron is a better conductor of electricity.

Correct Answer: Soft iron is easier to magnetize and demagnetize.

What is the main principle behind the operation of a telegraph system?

The use of static electricity
The transmission of light signals
The use of a closed-circuit battery
The use of electromagnets to attract a hammer

Correct Answer: The use of a closed-circuit battery

What is the primary function of the electromagnet in an electric bell?

To provide insulation for the circuit
To attract the hammer to the bell
To produce a ringing sound
To regulate the flow of current

Correct Answer: To attract the hammer to the bell

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