Science exam 2

Question 1

Definition of voltage

Answer 1

Voltage is the pressure from an electrical circuit’s power source that pushes charged electrons (current) through a conducting loop, enabling them to do work such as illuminating a light.

Question 2

Definition of current

Answer 2

Current is a flow of electrical charge carriers, usually electrons or electron-deficient atoms.

Question 3

Definition of resistance

Answer 3

is a measure of how difficult it is for current to flow.

Question 4

Definition of Potential difference

Answer 4

Another name for voltage, the difference in electric potential between two points in a circuit.

Question 5

difference between series and parallel circuits

Answer 5

In a series circuit, the total voltage from the battery is divided between the components. For example, if you have a 6V battery and two lamps, each lamp might get 3V.

In a parallel circuit, each component gets the full voltage from the battery. So if you have a 6V battery, each lamp gets 6V.

Question 6

series circuit

Answer 6

A series circuit is a type of electrical circuit where all components are connected in a single path, the same current flows through each component the voltage is split between the components . If one part of the circuit breaks, the entire circuit stops working.

Question 7

parallel circuit

Answer 7

A parallel circuit is an electrical circuit where components are connected in multiple paths, the current can flow through more than one path. Each component receives the full voltage from the power source, and if one path is broken, the other paths can still function.

Question 8

ohms law

Answer 8

formular:
V= Voltage
I= Current
R= Resistance

V= I x R
I= V divide R
R= V divide I

Question 9

Light waves

Answer 9

Light Waves: Light waves are transverse waves, meaning they oscillate perpendicular to the direction of travel.

Question 10

How light waves are measured

Answer 10

Measurement: Wavelength and frequency are used to measure light waves.

Question 11

Speed of light in a vacuum

Answer 11

Speed of Light: The speed of light in a vacuum is approximately
3×100000000
3×10 8
meters per second.

Question 12

light made of particles

Answer 12

Light is also made up of particles called photons.

Question 13

terms associated with reflection of light.

Answer 13

Reflection Terms: Angle of incidence, angle of reflection, normal, incident ray, reflected ray.

Question 14

The relationship between the angle of incidence and the angle of reflection.

Answer 14

Law of Reflection: The angle of incidence i
i is equal to the angle of reflection r

Question 15

refraction

Answer 15

Refraction: The bending of light as it passes from one medium to another due to a change in speed.

Question 16

why objects look distorted or closer when light is refracted through a medium such as water.

Answer 16

Distortion: Objects look distorted or closer in water because light slows down and bends when it enters a denser medium, like water, changing the perceived position of the object.

Question 17

Define refractive index and how it applies to bending of light.

Answer 17

Refractive Index: A measure of how much light slows down and bends when entering a medium. It is calculated by the ratio of the speed of light in a vacuum to the speed of light in the medium.

Question 18

Identify the primary and secondary colors of light.

Answer 18

Primary Colors: Red, Green, Blue (RGB).

Secondary Colors: Cyan, Magenta, Yellow (formed by mixing primary colors).

Question 19

Understand how colors in white light are reflected (or absorbed) in opaque objects.

Answer 19

Reflection/Absorption: Opaque objects reflect certain wavelengths (colors) of light and absorb others. The color you see is the color of light reflected.

Question 20

Optic fibres and how they work

Answer 20

Optic fibers are thin strands of glass or plastic used to transmit data as light signals. They work through a process called total internal reflection, where light continuously bounces off the walls of the fiber, allowing data to travel quickly over long distances with minimal signal loss.

Question 21

how do microwave ovens work

Answer 21

Microwave ovens work by generating electromagnetic waves that cause water molecules in food to vibrate, producing heat through friction that cooks the food from the inside out.

Question 22

the benefits of optic fibers over conventional wires in communication systems.

Answer 22

Benefits of Optic Fibers: Higher bandwidth, faster data transmission, and less signal degradation compared to conventional wires.

Question 23

definition of transparent

Answer 23

A material that allows light to pass through it so that objects behind can be clearly seen (e.g., glass).

Question 24

definition of Translucent

Answer 24

A material that allows some light to pass through, but not enough to see through it clearly (e.g., frosted glass).

Question 25

definition of Opaque

Answer 25

A material that does not allow light to pass through it (e.g., wood).

Question 26

Law of Reflection

Answer 26

The angle of incidence (
i
i) is equal to the angle of reflection (
r
r).

Question 27

Speed in vacuum over speed in medium

Answer 27

n = c over v
N is the refractive index
C is the speed of light in a vacuum
V is the speed of light in a medium

Question 28

What are the advantages of optic fibres

Answer 28

High data transmission
Less signal loss
Immunity to electromagnetic wave