OCR Physics - P5 Space for reflection

B5 revison cards. Covering all B5. 

Check out my other stuff, I revise by making these, so they are for all sciences as I revise. 

HideShow resource information

Uses of artifical satellites?

• GPS.

• Communications.

• Military uses.

• Scientific research.

• Weather forecasting.

1 of 27

The lower the satellite is from the earth, the wha

• Lower orbit satalites orbit faster around the earth because the gravitational force is stronger.

• Orbital Period speed =  Distance from earth

2 of 27

What is gravity?

• Anything with mass exerts a force of gravity. 

• The greater the mass the greater the force.

3 of 27

What is a geostationary satellite?

• A geostationary satellite is one which stays over a fixed point across the equator. 

• It orbits the earth every 24 hours. 

4 of 27

Uses for low polar/high geostationary orbit satell

Low Polar Orbit: 

• Weather forecasting.

• Mapping the earth.

High Geostationary Orbit:

• Weather forecasting.

• Communications.

5 of 27

Relative speed of moving objects.

• Two objects moving in the same direction have lower relative speed.

• Two objects moving in the opposite direction have a higher relative speed. 

6 of 27

Vector and Scalar quantities?

A vector has both magnitude and direction. A scalar has only magnitude. 


• Velocity

• Acceleration

• Momentum 

• Friction 


• Volume

• Mass

• Density

• Speed

• Area

7 of 27

How to calculate same/opposite direction vector eq



8 of 27

How to calculate not same/opposite direction vecto



9 of 27
10 of 27

What is amplification?

• An amplification gives a signal more energy.

11 of 27


• When waves meet a gap in a barrier, they carry on through the gap.

• The waves spread out into the area beyond the gap.

• The extent of spreading depends on the width of the gap compared with the wavelength of the waves.


12 of 27

What is frequency?

• This is the number of oscillations per second.

13 of 27

What is the ionosphere?

• A region of atmosphere where molecules have been ionised by sun radiation.

14 of 27

How do horizontal projectiles work?

• Horizontal motion is not affected by gravity (vertical motion) 

• Horizontal motion is constant in projectiles. 

• The path of a projectile is always a parabola. 

Example of a parabola: 


15 of 27

How to work out momentum?

• Momentum = Mass * Velocity 

• Momentum (kg m/s) = Mass (kg) * Velocity (m/s)

• The greater the mass of an object the larger the momentum.

• Without external forces momentum is conserved.

16 of 27

Working out recoil?

1.  Recoil m/s = mass of bullet * velocity of bullet / mass of gun 


17 of 27

Working out newtons of force?

• Force acting (N) = change in momentum / time taken for change to happen 


change in momentum = 100 kg m/s 

time taken = 0.2 s

newtons of force = 100 / 0.2 = 500 newtons of force 

Note: this only applies when the change in momentum is constant over time. 

18 of 27

What frequency waves travel which routes?

Ground Waves:

• Travel in close contact with the ground.

• Long wave/medium radio waves. (3 MHz)

Sky Waves:

• Short wave radio waves. (30 MHz)

• Travel up to the ionosphere where they reflect. 

• Allows them to travel furthur distances.

• Overcomes the curvature of the earth. 

Space Waves:

• Microwave signals (3000 MHz)

• Pass through the ionosphere and are reflected off satellites orbiting the earth. 

19 of 27

What are transverse waves? How can they be filtere

• All electromagnetic waves are traverse.

• Transverse waves can be polarized to prevent the passing of waves from horizontal sources: 

• So you can only see things from light sources you are looking at an angle. 

• This reduces glare. 

20 of 27

What order is the electromagnetic spectrum in?


21 of 27

What is refraction? Part 1

• Refraction is:


22 of 27

What is refraction? Part 2

• When a wave enters a denser medium, it is slowed down and bends towards the normal.

• When a wave enters a less dense medium, it speeds up and is bent away from the normal.

  • As usual, the normal is 90° from the object's surface.
  • As the light enters the dense glass, it bends towards the normal.
  • As the light leaves the glass to the less dense air, it bends away from the normal.
  • The refracted wave is called the emergent ray.
23 of 27

Critical angle and Total internal reflection is wh

• The point after which light will be reflected, rather then refracted is called the Critical angle.

• Light which is reflected back into the glass is called a total internal reflection.

24 of 27

How do fiber optics work?

• Fiber optics work due to cladding.

• The cladding (like mirrors) do not absorb light, they only reflect it.


25 of 27

Snell's Law is what?

• Snell’s law relates the angle of refraction to the angle of incidence as a light wave enters or leaves a more optically dense material.

                                              n = sin i/ sin r 

• n is the refractive index of the more dense material such as glass, water etc.

• If you know two of either, n, r or i, then this equation can be worked out.  

26 of 27

Convex and Concave lenses do what?

• Convex lenses focus light to converge towards a focal point.

• Concave lenses cause light to diverge and spread out.


27 of 27


No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Astronomy resources »