light

Question 1

What is light?

Answer 1

Light is a form of energy

Question 2

What are the properties of light?

Answer 2

1. Light travels 3 x 10 8 m/s through a vacuum
2. Light travels in straight lines
3. A shadow is formed when light is blocked

Question 3

What is a thin line of light?

Answer 3

A thin line of light is a ray of light

Question 4

What is a bundle of light called?

Answer 4

A bundle of light is called a beam of light

Question 5

What are the types of light beams?

Answer 5

1. parallel light rays ( spotlight on stage )
2. divergent rays = spread outwards ( lighthouse )
3. convergent rays = merge to a point ( glasses )

Question 6

give an explanation of an example of an object that uses convergent rays

Answer 6

The lenses in reading glasses converge light beams to single points

Question 7

What are the properties of a shadow?

Answer 7

1. A shadow is formed when light is blocked
2. A shadow takes the shape of an object that is blocking the path of light
3. An opaque object does not allow light to pass through, it cannot bend around an object and reach behind it

Question 8

How do we see?

Answer 8

1. Non-luminous objects:
   We see because the objects reflect light from light source into our eyes
2. Luminous objects:
   Luminous objects gives off light which enters our eyes

Question 9

What are the laws of reflection?

Answer 9

1. the incident ray, reflected ray and the normal at the pint of incidence all lie in the same plane
2. the angle of incidence equals to the angle of reflection

Question 10

what is a luminous object?

Answer 10

A luminous object emits light into our eyes which enable us to see them

Question 11

what is a non-luminous object?

Answer 11

A non-luminous object is not able to emit light but it reflects the light from the light source which enters our eyes, which is why we are able to see the.

Question 12

properties of a convex mirror and its uses?

Answer 12

The image produced by the convex mirror
1. is upright
2. is virtual ( cannot be formed on a screen/captured on the screen )
3. diminished ( smaller than the real size )

It is used as a rear-view mirrors in cars and at road junction. The image produced is smaller than the real size, therefore, the mirror is able to provide a larger field of vision. Shopkeepers place them in areas of their shop to monitor a large area of the shop from one location. The convex mirror gives them a diminished image that gives a large field of vision to spot potential shop lifters

Question 13

Properties of a concave mirrors and its uses?

Answer 13

The image produced by the concave mirrors are:
1. virtual
2. upright
3. magnified ( bigger than the real object )

Dentist uses concave mirrors which gives them a magnified image of the teeth so that they can see focused areas clearly for them to spot any potential teeth problems. Concave mirrors are also used in the headlights of the car to focus the lights