Historical Figures and Contemporary Physics

Question 1

Galileo Galilei

Answer 1

bodies dropped from the same height will all fall with the same acceleration, g. Principle of inertia: the natural state of motion is uniform constant velocity

Question 2

Isaac Newton

Answer 2

1st law of motion: the natural state of motion is constant velocity UNLESS acted upon by an unbalanced force. 2nd law of motion: sigmaF = ma 3rd law of motion: action-reaction pair. Law of gravity, Fg = Gm1m2/r^2

Question 3

James Watt

Answer 3

developed the concept of power

Question 4

Johann Kepler

Answer 4

3 laws of planetary motion

Question 5

Charles-Augustin de Coulomb

Answer 5

Coulomb’s law: Fe = kq1q2/r^2

Question 6

Georg Simon Ohm

Answer 6

ohm’s law: V = IR

Question 7

Michael Faraday

Answer 7

electromagnetic fields: introduced the way to visualize electric and magnetic fields as lines extending through space. Electromagnetic induction: moving magnet through current (Etc…)

Question 8

Heinrich lenz

Answer 8

lenz’s law: dictated the direction of an induced current in a closed loop of conducting material, based on conversation of energy

Question 9

James Maxwell

Answer 9

electromagnetic waves: showed that light is an electromagnetic wave moving at the speed of light

Question 10

Thomas Young

Answer 10

double-slit experiment. Proved that light is a wave phenomenon

Question 11

Christian doppler

Answer 11

doppler effect: shift in wavelength and frequency when the source is moving toward/away from an observer

Question 12

Lord Kelvin

Answer 12

abs. zero

Question 13

James Joule

Answer 13

showed that heat and work are both methods of adding energy to a system

Question 14

Albert Michaelson and Edward Morley

Answer 14

attempted to detect ether using an INTERFEROMETER (failure->relativity)

Question 15

J.J. Thomson

Answer 15

discovered the electron. (plum-pudding model -> atom has overall positive charge with negatively charged electrons distributed randomly throughout the atom

Question 16

Max Planck

Answer 16

founder of quantum theory: derived planck’s constant and said that light energy can be emitted only in multiples of specific quantities.

Question 17

Albert Einstein

Answer 17

photoelectric effect: light acts like a particle (photon). E = hf. special relativity, mass-energy equivalence (E = mc^2)

Question 18

Ernest Rutherford

Answer 18

gold foil experiment: fired alpha particles at a very thin piece of gold foil. showed that the atom is mostly empty space consisting of a dense positively charged nucleus surrounded by orbiting electrons

Question 19

Niels Bohr

Answer 19

Planetary model of the atom, including specific energy levels. Shows why electron orbits do not decay and fall into the nucleus.

Question 20

Microprocessor

Answer 20

a complex, single circuit consisting of many miniaturized components

Question 21

Semiconductor

Answer 21

can be either conductor or insulator

Question 22

Superconductor

Answer 22

has zero electrical resistance when cooled below a critical temperature

Question 23

Transistor

Answer 23

used in integrated circuits of all modern electrical devices. can act as a switch.