1.
What is the primary function of a Van de Graaff generator?
Correct Answer
C. Generate high voltages
Explanation
The primary function of a Van de Graaff generator is to generate high voltages. It achieves this by accumulating static electricity and transferring it to a large metal dome, creating a high electric potential difference. This potential difference can reach tens of thousands or even hundreds of thousands of volts, making Van de Graaff generators valuable tools for various scientific experiments, such as particle acceleration and electrostatic demonstrations.
2.
How does a Van de Graaff generator accumulate static electricity?
Correct Answer
B. By frictional contact
Explanation
A Van de Graaff generator accumulates static electricity through frictional contact. This typically involves rubbing two different materials together, such as a rubber belt and a metal roller, which results in the transfer of electrons and the buildup of charge. The friction between the materials causes electrons to be stripped from one surface and transferred to the other, creating an imbalance of charge that accumulates on the surface of the belt.
3.
What component of a Van de Graaff generator is responsible for creating the electric potential difference?
Correct Answer
C. Belt and pulleys
Explanation
The electric potential difference in a Van de Graaff generator is created by the belt and pulley system. As the belt moves over the pulleys, it becomes charged due to friction and carries charge to the dome, creating the potential difference. This potential difference is crucial for generating high voltages, as it allows the generator to accumulate and store electrical energy, which can then be discharged in controlled experiments.
4.
What material is commonly used for the belt in a Van de Graaff generator?
Correct Answer
D. Nylon
Explanation
Nylon is commonly used for the belt in a Van de Graaff generator. Nylon is a good insulator and has the necessary properties to generate and transfer charge effectively. It is durable, flexible, and resistant to abrasion, making it ideal for use in the belt of a Van de Graaff generator. Additionally, nylon's low conductivity helps to prevent leakage of charge, ensuring that the generator operates efficiently.
5.
What phenomenon occurs when the electric potential difference in a Van de Graaff generator becomes too high?
Correct Answer
B. Static discharge
Explanation
When the electric potential difference in a Van de Graaff generator becomes too high, static discharge occurs. This is when the accumulated charge jumps from the generator to a nearby conductor, often producing a visible spark. Static discharge is a natural phenomenon that occurs when the electric field between the charged dome of the generator and the surrounding environment becomes strong enough to overcome the resistance of the air. It serves as a safety mechanism to prevent the buildup of excessively high voltages, which could damage the generator or cause harm to nearby objects or individuals.
6.
What principle of physics does the Van de Graaff generator demonstrate?
Correct Answer
B. Coulomb's law
Explanation
The Van de Graaff generator demonstrates Coulomb's law, which describes the electrostatic force between charged objects. As charge accumulates on the dome, it creates an electric field that exerts a force on nearby charges. Coulomb's law states that the force between two charged objects is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. This principle governs the behavior of charged particles in the electric fields generated by the Van de Graaff generator, providing a fundamental understanding of electrostatic interactions.
7.
What is the purpose of the metal dome at the top of a Van de Graaff generator?
Correct Answer
A. To contain the electric charge
Explanation
The metal dome at the top of a Van de Graaff generator serves to contain the electric charge. It provides a large surface area for charge accumulation and helps to maintain a high electric potential difference. Without the dome, the accumulated charge would dissipate into the surrounding environment, reducing the effectiveness of the generator. Additionally, the dome helps to focus the electric field, allowing for more efficient charge transfer and higher voltages.
8.
What is the typical voltage output range of a Van de Graaff generator?
Correct Answer
D. 10,000-100,000 volts
Explanation
The typical voltage output range of a Van de Graaff generator is 10,000-100,000 volts. Some larger models can produce even higher voltages for specialized experiments. These high voltages are generated through the accumulation and transfer of static electricity, facilitated by the belt and pulley system of the generator. The voltage output of a Van de Graaff generator is influenced by factors such as the size of the generator, the speed of the belt, and the materials used in its construction.
9.
What are Van de Graaff generators commonly used for in scientific experiments?
Correct Answer
C. Accelerating particles
Explanation
Van de Graaff generators are commonly used in scientific experiments to accelerate particles. They are often employed in particle accelerators to generate high-energy beams for research in nuclear physics and particle physics. The principle behind particle acceleration in a Van de Graaff generator is based on the repulsion between like charges. As charge accumulates on the dome of the generator, it creates an electric field that accelerates charged particles to high speeds. These accelerated particles can then be used for various experiments, such as studying the structure of atomic nuclei or investigating the properties of subatomic particles.
10.
What safety precaution is important when operating a Van de Graaff generator?
Correct Answer
C. Isolating the generator from ground
Explanation
A key safety precaution when operating a Van de Graaff generator is isolating it from ground. This helps to prevent electric shocks and ensures that the generator operates safely and effectively. Isolating the generator from ground means that there is no direct path for electric current to flow from the generator to the ground, reducing the risk of electrical accidents. This can be achieved by placing the generator on insulating materials, such as rubber or plastic, and ensuring that it is not in contact with any conductive surfaces. Additionally, operators should avoid touching the generator while it is in operation and should follow all safety guidelines provided by the manufacturer.