Physics Test 2

electric field lines properties

1-The lines indicate the direction of 𝐸 2-Electric field lines start on positive charges and end on negative charges. 3-The number of lines crossing unit area perpendicular to the lines is proportional to the magnitude of the electric field. 4-The closer together the lines, the stronger the electric field.

PRACTICE An empty capacitor is connected to a battery and charged up. While it is still connected to the battery, a slab of dielectric material inserted between the plates of the capacitor. Will Q: A) increase B) remain the same C) decrease?

A

equipotential surface

An equipotential surface is one on which all points are at the same potential. The potential difference between any two points on the equipotential surface is zero, so no work is required to move a charge on the surface.

PRACTICE An empty capacitor is connected to a battery and charged up. The capacitor is then disconnected from the battery, and a slab of dielectric material is inserted between the plates. Does the potential difference across the plates: A) increase B) remain the same C) decrease

C

electric field

Electric field is a region around a charge which a force can be exerted on other charges.

Coulomb's Law

F=K (q₁*q₂/r²), magnitude of force between two charges. SI unit of charge is the coulomb (C) 𝑘 = 8.99 × 10^9 𝑁. 𝑚^2/𝐶^2 ≈ 9 × 10^9 𝑁. 𝑚^2 /𝐶^2

Equipotential surfaces are:

Perpendicular to the electric field lines. Always continuous and never end.

capacitor

a device that can store electric charge, and normally consists of two conducting objects placed near each other but not touching

electrical field lines

are imaginary lines that show the direction of the electric field. The direction of the electric field lines for positive charge is outward and inward for negative charge.

Gauss Law

law that describe the relationship between a charge distribution and the electric field it produces. This law can be used to find the electric field of a charge distribution.

law of conservation of electric charge

states that the net amount of electric charge produced in any process is zero

electrical charge

the physical property of matter that causes it to experience a force when placed in the presence of another charge. There are positive and negative charges.

conduction

the process by which heat or electricity is directly transmitted through a substance when there is a difference of temperature or of electrical potential between adjoining regions, without movement of the material.

battery is composed of

two different electrodes and electrolyte solution.

Induction

when two objects do not touch, the free electrons move towards the external charge leaving the opposite charge at the opposite end