Science Revision Cards

What is an Isotope?

Atoms of an element that contain different numbers of neutrons in their nuclei.

REMEMBER: Isotopes always have 6 protons but different numbers of neutrons.

e.g. Carbon 12           Carbon 14

       6 protons             6 protons                                                                                    6 neutrons           8 neutrons

What do I mean when I "decomission" a power plant?

To decomission a powerplant is where you dismantle and remove radioactive material (waste) safely.

What is the "Big Bang" theory?

• This is the theory that the universe was created in a massive explosion (the big bang).
• The universe has been exanding ever since this explosion.

What is the "Red Shift"?

• redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum. More generally, where an observer detects electromagnetic radiation outside the visible spectrum, "redder" amounts to a technical shorthand for "increase in electromagnetic wavelength" — which also implies lower frequency and photon energy in accord with, respectively, the wave and quantum theories of light.
• The faster the speed of the star or galaxy the greater the redshift.

What is the equation for efficiency?

Efficiency = useful energy suppied by motor / total energy supplied by motor

What type of wave is used to send information to and from satelites?(1 mark)

Microwaves