Physics Defintions

Question 1

Static Friction

Answer 1

force opposes tendency motion stationary object rel to surface

Question 2

Kinetic Friction

Answer 2

force opposes tendency motion moving object rel to surface

Question 3

Inertia

Answer 3

Property resist change in state of rest or const vel

Question 4

Newtons 1

Answer 4

const vel/rest remains until fnet>0

Question 5

Newtons 2

Answer 5

When fnet acts, obj a in direc of fnet. A direc prop fnet inverse prop mass

Question 6

Newtons 3

Answer 6

Obj A exerts force on obj B, obj B exerts = mag opp direc on obj A

Question 7

Grav

Answer 7

Every body attract every other body force direc prop product masses inverse prop square distance between

Question 8

Coloumbs

Answer 8

Electrostatic f of attrac/repulse exerted by one charge on another obj direc prop product charges inverse prop square distance between

Question 9

Isolated system

Answer 9

a system where resultant external force is zero.

Question 10

Electric Field

Answer 10

Region in space where electrostatic charge experiences a force

Question 11

Electric Field Strength/At a point

Answer 11

electrostatic force experienced per unit positive charge placed at that point

Question 12

Ohms Law

Answer 12

Current along a conductor direc prop to potential difference along the conductor provided temp constant

Question 13

Power

Answer 13

Rate at which work is done

Question 14

Resistance

Answer 14

Ratio of potential difference across a resistor to current in the resistor

Question 15

Potential Difference

Answer 15

Energy transferred per unit charge flowing between 2 points through a conductor

Question 16

Emf

Answer 16

Energy provided by battery per unit charge flowing through the battery

Question 17

Internal Resistance

Answer 17

Resistance within a battery when current is flowing which causes a decrease in potential difference that the battery can supply to the external circuit

Question 18

Momentum

Answer 18

Product of m and v

Question 19

Newtons 2 in terms of momentum

Answer 19

The resultant/net force acting on an object is equal to the rate of change of momentum of the object in the direction of the resultant/net force.

Question 20

Impulse

Answer 20

product of the resultant/net force acting on an object and the time the resultant/net force acts on the object

Question 21

Elastic Collision

Answer 21

A collision in which total momentum and kinetic energy are conserved

Question 22

Projectile

Answer 22

obj given vi after which fg only force on it

Question 23

Free fall

Answer 23

obj only under fg

Question 24

Work energy theorem

Answer 24

Net work done = delta EK

Question 25

Conservative force

Answer 25

A force where work done indep path taken (Fg)

Question 26

Conservation emech

Answer 26

Emech in isolated system remains constant

Question 27

Doppler

Answer 27

Apparent change in frequency of sound detected by listener as result of rel motion between source of sound and listener

Question 28

Use of doppler

Answer 28

Doppler Flow Meter - med field for rate of blood flow Doppler Foetal Monitor - US Doppler Radar Gun - Speed of moving vehicle

Question 29

Red Shift

Answer 29

When star moves away from earth light waves behind star become spread out ie wavelength inc freq dec. Light shifts towards the red end of spectrum

Question 30

Blue Shift

Answer 30

When start moves toward earth light waves ahead of star become compressed ie wavelength dec freq inc. Light towards blue end of spectrum

Question 31

Why universe expand?

Answer 31

Light from most galaxies observed is redshifted implying expansion