Light and Electricity Practice Flashcards

Comprehensive practice flashcards covering properties of light, reflection, refraction, and introductory electricity principles such as Ohm's Law and static charges based on lecture notes.

What is Light?

Light is a form of energy which is visible to the human eye.

What is the speed of light?

$$3 \times 10^8\,m/s$$

How does light travel?

At different speeds through different media and in Straight Lines.

What is the order of mediums provided in the notes?

Air - Ice Water Glass - Dimond.

What is a Transparent material?

Materials that allow all light to pass through

What is a Translucent Material?

Materials that allow almost all light to pass through

What is an Opaque material?

Materials that don't allow light to pass through

What is a Shadow?

A region of darkness formed when a part of light is balanced by an opaque object.

What are the factors of a point sourse of light?

1. Unsformed shadow (umbra) 2. Totally dark 3. Sharp out line.

What are factors of an extended source of light?

1. Umbra anda a penumbra. 2. Varies in brightness 3. No shap outlines.

What happens to your shadow when you walk closer to a lamp?

Your shadow gets shorter and is behand you.

What happens when you walk past a lamp?

Your shadow gets longer and is now infront of you

What happens during a Solar Eclipse?

Sun cast a shadow of the moon on the earth during a New Moon in the day.

What happens during a Lunar Eclipse?

Sun casts a shadow of the earth on the moon during a Fall moon in the night.

What are the laws of reflection?

1. The angle of incidence is equal to the angle of reflection ($i=r$) 2. The incidentray, the normal and the reflected ray at the point of incidence all lie in the same plane

What is reflection?

Reflection is the bouncing of light off the surface that it strikes.

What is refraction?

Refraction is the bending of light when it is passed from one medium to another.

What happens when light travels from an optically dense medium to an optically denser medium?

Light bends toward the normal.

What happens when light travels from an optically dense medium to an optically less dense medium?

Light bends away from the normal.

What happens if light enters a medium at a right angle?

Light passes right through without refracting.

What light is refracted the most?

Red

If a lazer light is aimed at a glass block along the normal what angle will emerge?

$$0^\circ$$

The refractive index of glass is $1.5$, what does it mean?

Light travels $1.5$ times slower in glass than in our.

The retracted index of our is?

$$1$$

The refractive index of glass is?

$$1.5$$

What is Snell's law?

1. The normal, incedent ray and the refracted ray all lie in the same plane at the point of incidence

2. The ratio of the sine of the angle of incidence ($\theta_1$) is equal to the sine angle of refraction ($\theta_2$) of the refractive indices of the two media. $\frac{\sin(i)}{\sin(r)} = \text{constant}$.

In the event the line of the graph is straight, why is that?

Because Sine i is directly positioned to sine r

What is Static electricity?

The buildup of an electric charge on the surface of an object caused usually by friction.

What is Current electricity?

The rate of flow of electric charge through a conclucher or space

What is a Conductor?

A conductor is an object where electrons pass through

What is an Insulator?

An object where electrically charged elections are unable to pass through.

What is Ohm's law?

1. The current through an concluctor between two points is directly porportional to the potential difference across those points provided the temperature remains Constant. 2. $V = I \times R$

What charge is Glass?

Positie

What charge is Polythene?

Megatule

If an object obtens electrical charge by induction it is?

An uncharged body.

What god gives charge of the same sign?

Conductor.

What test determins a charge on a body?

Repulsion

Conventional Current flows from?

Positure to Negative.

What are the characteristics of images formed by a plane mirror?

1. The same size of the object 2. The same distance behind the mirror as the object 3. Virtual. 4. Laterally inverted.

What is the angle of reflection?

The angle between the reflected ray and the normal.

What is the angle of incidence?

The angle between the incident ray and the normal

What is the reflected ray?

The ray that hits or strikes the surface of the mirror.

What is the normal?

The ray perpendicular to the mirrer