Refraction/Reflection, Electromagnets, Space, Particle theory + Pressure, Static electricity Flashcards
(32 cards)
What is the equation of pressure?
Pressure= Force(N) divided by Area (m squared) Example = 12000N divided by 3.0 m squared = 4000 Pa
What is an electromagnet?
A solenoid in which the insulated wire is wrapped around an iron bar (the core).
Write the force that can cause dust and gas particles to attract each other…
Gravitational attraction (force of gravity).
What happened once the sun was formed?
Once the sun was formed, its heat evaporated ice and drove gas away from the inner solar system, leaving rocks behind. The rocky planets formed near the sun and the gas giant planets formed further away.
Give three ways that the strength of an electromagnet can be increased by…
- More coils
- Increase current
- Add iron core
How does an electric bell work?
When an electric bell is connected to a battery, the iron armature goes toward the electromagnet. The make-and-break switch opens and the electromagnet turns off. The iron armature springs back and the make-and-break switch closes again, the cycle repeats itself.
What are the three main uses of static electricity?
- Photocopiers
- Defibrillators
- Spray painting
How does spray painting work?
Paint is positively charged. The paint spreads out because the charges repel each other. This is because the object (for example a bike) is negatively charged and when the paint is applied it stays on the object as the two charges attract.
What is electricity explained by?
Electrons
What is static electricity caused by?
Friction
Where are protons and neutrons found?
In the nucleus
What is charge measured in?
Coulombs (c)
One similarity between a comet and an asteroid…
They both orbit the sun.
Why does a white dwarf become a black dwarf?
Because the star has gone colder and has faded out.
Where did the energy that heated the stars come from? (1 mark)
The energy that heated stars came from nuclear fusion, which involves two atomic nuclei joining together.
What will happen to the sun after its present stage? (3 marks)
It will turn into a red giant once all the Hydrogen has fused to helium and made elements up to iron in its core.
It will then get rid of the layer of dust surrounding it (planetary nebula) and turn into a white dwarf.
Before it cools down and becomes a black dwarf.
Define a black hole…
A region in space which has a gravitational field so intense that no matter or radiation can escape.
What is meant by refraction?
Light changes direction when it changes speed.
What happens when a ray of light goes through a block of glass?
Light slows and the ray bends towards the normal.
What happens when the light ray leaves the glass?
The light speeds up and the ray bends away from the normal.
The angle of reflection is always…
equal to the angle of incidence.
What is a red shift?
A red shift is when the wavelengths of the waves are increased. The light waves are stretched out if a galaxy is moving away from you.
What type of satellite is the earth’s moon?
Natural.
What is the force on the orbiting body?
Force of gravitational attraction between it and the larger body.
