1.7 Introduction to Charge and Electric Forces

These flashcards cover key concepts related to charge, electric forces, and their properties.

What is charge in the context of physics?

Charge is a property of matter that exists in two types: positive and negative.

What are the two types of charge?

Positive charge and negative charge.

What is the unit of charge?

The unit of charge is the Coulomb, symbolized by 'C'.

What is Coulomb's force?

Coulomb's force describes the electric force between two charges, given by the equation F = k * (q1 * q2) / r^2.

Is electric force a vector or a scalar quantity?

Electric force is a vector quantity.

How does the force between two charges change with distance?

The force decreases rapidly as the distance increases, following the inverse square law (1/r^2).

What happens to the force when charges are similar?

Like charges repel each other.

What is a conductor?

A conductor is a material that allows electrons to move freely.

What is an insulator?

An insulator is a material where electrons are tightly bound and do not move freely.

What is the role of valence electrons in conductors?

Valence electrons in conductors can move freely, allowing for the conduction of electricity.

What is static electricity?

Static electricity is the stationary electric charge that can accumulate on an object.

How can charge be transferred by rubbing two materials together?

One material can gain electrons, becoming negatively charged, while the other loses electrons, becoming positively charged.

What is contact charging?

Contact charging involves transferring charge by touching a charged object to a neutral conductor.

What is optical induction?

Optical induction is the process where a charge induces polarization in a neutral object without direct contact.

What is grounding in electrical systems?

Grounding connects an electrical system to the earth, providing a path for excess electrons.

What occurs during grounding?

Grounding can draw excess charge away from or supply charge to a system, stabilizing it.

What is the relationship between polarization and charge separation?

Polarization occurs when the distribution of charges within an object becomes uneven due to an external electric field.

What is the significance of a positive charge rod being brought near a neutral object?

The positive charge induces a redistribution of charges in the neutral object, creating a net attraction.

What happens during electrostatic equilibrium?

Electrostatic equilibrium is reached when the charges in an object are evenly distributed after touching and separating conductive objects.

How does bringing a charged object close to a conductor lead to charge transfer?

The proximity of a charged object can cause electrons in the conductor to move and redistribute, transferring charge when contact occurs.

What happens when two identical conductive spheres touch?

They share their charge evenly, resulting in equal charge on both spheres when separated.

What charge results from touching a negatively charged sphere to a positively charged sphere?

They will share charge and, when separated, exhibit positive and negative charges based on the initial charge conditions.

Define the concept of polarization of molecules in materials.

Polarization occurs when the distribution of electric charges within molecules shifts in response to an external electric field.

What is the effect of bringing a negatively charged rod close to a neutral wall?

Electrons in the wall are repelled, leaving positive charges closer to the rod, creating an attractive force.

How can two spheres remain neutral after induction?

If they are separated before charge redistribution occurs, they maintain their neutral state.

What determines if an object will become positively or negatively charged?

The material's affinity for electrons determines if it will lose or gain electrons upon contact with another material.

What is the role of electrons in metals compared to insulators?

Electrons in metals are free to move, while in insulators, they remain bound to their nuclei.

What happens when two charged objects are brought close together?

Their electric fields interact, resulting in forces that can attract or repel them depending on the charges.

What is an example of a practical application of grounding in electrical devices?

Grounding is used to prevent electrical shock by providing a safe path for excess current.

What role do insulators play in preventing charge movement?

Insulators limit electron movement across materials, keeping them from losing or gaining charge.

In the context of charge, what is an electric field?

An electric field is the region around a charged object where other charges experience a force.