Physics G485 definitions

• Created by: Emily B
• Created on: 19-02-13 22:43
Electric Field Strength
Force per unit positive charge
1 of 34
Magnetic Flux Density
The strength of the magnetic field
2 of 34
Tesla
The SI unit for magnetic flux density. 1T = 1NA^-1m^-1
3 of 34
Magnetic Flux
The product of magnetic flux density normal to a circuit and the cross-sectional area of the circuit. unit is Weber's
4 of 34
The product of the magnetic flux and the number of terms
5 of 34
The emf induced is equal to the rate of change of magnetic flux linkage or the rate of flux cutting
6 of 34
Lenz's Law
The induced current or EMF is in a direction so as to produce effects which oppose the change producing it
7 of 34
Capacitance
The ratio of change stored by a capacitor to the PD across it
8 of 34
Unit of capacitance. 1F = 1CV^-1
9 of 34
Time Constant of a circuit
The time taken for the current, charge stored or PD to fall to 1/e (about 37%) when a capacitor discharges through a resistor. It is also equal to the product of capacitance and resistance
10 of 34
Coulomb's Law
Any two point charges exert an electrical force on each other that is proportional to the product of their charges and inversely proportional to the square of the distance between them
11 of 34
Newton's Law of Gravitation
Any two point masses attract each other with a force that is proportional to the sum of their masses and inversely proportional the square of their seperation
12 of 34
Nucleon number
The number of protons and neutrons in the nucleus of an atom
13 of 34
Isotopes
Nuclei of the same element with a different number of of neutrons but the same number of protons
14 of 34
Activity
The rate of decay or disintegration of nuclei in a radioactive sample
15 of 34
Decay Constant
The constant for an isotope that appears in the equation A = lambda*N. It is equal to the probability of an isotope decaying per unit time interval
16 of 34
Half-Life
The mean time taken for half the number of active nuclei in a radioactive sample to decay
17 of 34
Binding Energy
The minimum external energy required to seperate all the neutrons and protons of a nucleus
18 of 34
Intensity
Power per unit cross-sectional area
19 of 34
For an infinite, uniform and static universe, the night sky should be bright because of light received in all direction from stars
20 of 34
Hubble's Constant
The ratio of the speed of a receding galaxy to its distance from the observer. =v/x
21 of 34
Cosmological Principle
A principle that states that the universe has the same large-scale structure when observed from any point in the universe
22 of 34
Critical Density
The density of the university that will give rise to a flat universe.
23 of 34
Black Hole
The remnant of a massive star formed as a result of matter collapsing to a singular point. The density of a black hole is so intense that even light cannot escape from it.
24 of 34
X-rays produced when electrons are decelerated
25 of 34
Chandrasekhar limit
The maximum mass of a white dwarf - about 1.4 solar masses
26 of 34
Closed universe
A model of the universe in which gravitational force is strong enough to halt its expansion and reverse the process towards a Big Crunch
27 of 34
Dark matter
Matter that emits or reflects little EM radiation making it very difficult to detect
28 of 34
Electron Degeneracy Pressure
Pressure created by closely packed electrons in a white dwarf due to Pauli's exclusion principle
29 of 34
Larmor Frequency
The frequency of precession of nuclei in an external magnetic field
30 of 34
Light year
The distance travelled by light in one year. =9.5x10^15 m
31 of 34
Metastable
Describes a nucleus that is unstable but relatively long-lived state
32 of 34
Open Universe
A model of the universe in which gravitational force cannot halt the expansion of matter.
33 of 34
Redshift
The shifting of the entire spectrum of a receding source to longer wavelengths
34 of 34

Other cards in this set

Card 2

Front

The strength of the magnetic field

Back

Magnetic Flux Density

Card 3

Front

The SI unit for magnetic flux density. 1T = 1NA^-1m^-1

Card 4

Front

The product of magnetic flux density normal to a circuit and the cross-sectional area of the circuit. unit is Weber's

Card 5

Front

The product of the magnetic flux and the number of terms

Back

Report

This so useful! thank you!

Report

incredible

Report