Flashcards in rest of science Deck (49):
how long does it take for the moon to orbit the earth
27 days and seven hrs
what are the different types of moon
whaxing and whaning
what are the stages in the cycle of the moon
new, whaxing cresant first quarter whaxing gibbous full whaning gibbous third quarter whaning cresent new...
what is lit up all of the time
one of the 2 halves of the moon is always light, and the other is always dark
what is a luner moon
the time between 1 new moon and the next
what is a solar eclipse
when the moon comes between the sun and the earth
what is a lunar eclipse
when the earth comes between the moon and the sun
why do we only ever see one side of the moon
because the time that the moon takes to spin on its axis is the same as the time it takes to spin around the earth
What does a source of light do?
It emits light
Give an example of a source of light
What is something that gives out light called
What do you call something that doesn't give out light
How do you see things?
They are reflected from light into your eyes
What does transparent mean?
You can see through it
What does translucent mean?
You can see through it, but not very clear
What does opaque mean?
A material which you can't see anything through
What do opaque materials produce
What can light travel through?
Most gases, some liquids and some solids
What is a vacuum?
An empty space
How fast does light travel
It travels at 300,000 km/s
How long does it take for light to travel from the sun to the earth
What is a light year
How far light travels in a year
What do you see in a mirror
What is an incident Ray?
The ray that hits the mirror from the Ray box
What is the Ray that reflects off the mirror called
What is the imaginary line at 90 degrees to the mirror called
What is the law of reflection
The angle of incidence is equal to the angle of reflection
What is specular reflection
Reflection from a smooth surface
What is diffuse scattering
Reflection from a rough surface
State the type of reflection when light hits a mirror
What is refraction
When the direction light is travelling changes
When does refraction happen?
Whenever light travels from one medium to another
What is the difference between reflection and refraction?
Reflection is where light is changing in straight lines. Refraction is where light changes the direction it is travelling in
What does a lens do?
It focuses the light and enables you to see
What are the lenses in your eyes called
Convex or converging
What is the focus point?
Where the Rays cross
What are drag forces
Water resistance and air resistance
How can you reduce drag forces
Being more streamlined
List some fuels
Petrol, diesel, hydrogen
What happens when fuels burn
A chemical reaction takes place, this is called combustion
What are fossil fuels
Made from underground or sea, they are non-renewable, They will run out one day
Name two reactants when hydrogen burns in air
Water and oxygen
What are oxidation reactions
When substances react with oxygen
What is an example of an oxidation reaction
What is a chemical reaction
Where atoms are rearranged to create new substances
Are chemical reactions reversible
Why are chemical reactions useful?
They are used to make medicine
What do chemical reactions also do?