Question

When a metal plate is given a positive charge, which of the following is taking place? a) Protons (positive charges) are transferred to the plate from another object. b) Electrons (negative charges) are transferred from the plate to another object. c) Electrons (negative charges) are transferred from the plate to another object, and protons (positive charges) are also transferred to the plate from another object. d) It depends on whether the object conveying the charge is a conductor or an insulator.

Short answer

a) Protons are transferred to the plate from another object. b) Electrons are transferred from the plate to another object. c) Both protons are transferred to the plate, and electrons are transferred away from it. d) The process depends on the conductor or insulator conveying the charge to the metal plate. Answer: b) Electrons are transferred from the plate to another object.

Step-by-step solution

Identify the facts and rules

When it comes to the transfer of charges in metal objects, we need to remember these basic facts: 1) Protons are positively charged, and their movement in solids, such as metals, is very limited. 2) Electrons are negatively charged, and they can easily move within metal objects. 3) In a neutral object, the number of protons and electrons is equal, so the charges cancel each other out. 4) A positive charge on an object can only be achieved by having a surplus of protons or by losing electrons.

Consider option a

Option a says that protons are transferred to the plate from another object. However, we know that protons have very limited movement in solids and cannot easily be transferred, especially in metals. Therefore, option a is not correct.

Consider option b

Option b states that electrons are transferred from the plate to another object. This would result in a loss of electrons in the metal plate, leading to an overall positive charge. As electrons are mobile within metals, this situation is possible. So, option b seems to be correct.

Consider option c

Option c suggests that both protons are transferred to the plate, and electrons are transferred away from it. Although the transfer of electrons from the plate is possible, the transfer of protons is not, as we established before. Therefore, option c is not correct.

Consider option d

Option d implies that the process depends on the conductor or insulator conveying the charge to the metal plate. However, in all cases, protons do not easily move in metals, while electrons can be transferred. So, option d is not correct.

Conclusion

Since the only option that corresponds to the behavior of protons and electrons in metals is option b (Electrons are transferred from the plate to another object), this is the correct answer. When a metal plate is given a positive charge, electrons are transferred away from the plate, leading to an overall positive charge due to the surplus of protons.

Key concepts

Electron Transfer

When it comes to understanding electric charge and how it is transferred, electron transfer plays a critical role. Electrons, which are negatively charged particles, can move freely between atoms in certain materials. This movement of electrons is key in determining whether an object becomes positively or negatively charged.

In metals, electrons can move quite freely. This is because metals have what we call a 'sea of electrons', meaning the electrons are not tightly bound to any particular atom. Instead, they can shift from one atom to another quite easily. This allows metals to conduct electricity very well. When a metal object like a plate gains a positive charge, it actually means it has lost some of its electrons.

• This creates an imbalance with more protons (positive charge) remaining, giving the object an overall positive charge.
• It's important to note that electrons, due to their small mass and freedom to move, are the primary carriers of charge in most electric processes.
• Conversely, gaining electrons would result in a negative charge.

Hence, whenever you hear about charging an object positively, think of it as a loss of electrons. This movement and transfer of electrons are key concepts behind many electrical principles.

Proton Movement

Protons are positively charged particles, fundamental to the structure of an atom. However, unlike electrons, protons are not typically involved in the transfer of charge in solid materials, like metals. This is due to their position within the atomic nucleus, which makes them relatively immobile.

The nucleus, housing the protons, is tightly bound and densely packed, and so any movement of protons within a solid requires a substantial amount of energy. That means:

• Protons generally stay fixed in place, anchoring the identity of an atom being either hydrogen, oxygen, and so on.
• In ordinary conditions, such as those we encounter in most electrical contexts or laboratory settings, protons do not move between objects.
• This immobility makes protons reliable markers of the identity of elements, but not participants in the daily transfer of electric charge.

When an object is charged positively, it is not because it has gained more protons, but instead, it loses electrons. Remember, electrons are the primary players in charge transfer, not protons.

Conductors and Insulators

In the realm of electric charge, understanding the materials involved is crucial, particularly the distinction between conductors and insulators. This distinction helps explain why and how various materials manage, transfer, or hold electric charges.

Conductors are materials where electric charge, or electrons, can move freely. This freedom is due to the loose hold on the electrons within the material, allowing them to pass from one atom to another with ease. Metals like copper and aluminum are classic examples of conductors.

• They allow easy movement of electrons, making them extremely effective for conveying electricity.
• The usefulness of conductors lies in their ability to efficiently transfer electrons from one end to another.

On the other hand, insulators are materials that resist the flow of electric charge. In these materials, electrons are tightly bound to their atoms and are not free to move. Rubber, plastic, and glass are well-known insulators.

• They prevent the transfer of electrons, effectively stopping the flow of electricity.
• This property makes insulators ideal for coating wires and electrical equipment, ensuring safety.

Understanding the behavior of conductors and insulators helps us harness electrical energy effectively and safely, guiding the design of circuits and the construction of various electronic devices.