Physics Quicksheets

Question 1

Current equation

Answer 1

I=Q/T in amperes(C/s)

Question 2

Emf

Answer 2

Electromotive force - “pressure to move” or the difference in potential (voltage) between 2 terminals

Question 3

Kirchoffs junction rule

Answer 3

I into the junction = I leaving the junction

Question 4

Kirchhoffs loop rule

Answer 4

For a closed circuit loop, sum of the voltage sources=sum of voltage(potential) drops cuz conservation of energy!

Question 5

vectors

Answer 5

physical quantities with both magnitude and direction (force, velocity)

Question 6

scalars

Answer 6

physical quantities with magnitude no direction (mass, speed)

Question 7

Displacement

Answer 7

change in position that goes in a straight-line path from the initial position to the final position, independent of the path taken

Question 8

average velocity

Answer 8

x/t (m/s)

Question 9

acceleration

Answer 9

rate of change of an object’s velocity v/t (m/s^2)

Question 10

kinematic equations

Answer 10

Question 11

projectile motion - vertical component =

-horizontal component =

Answer 11

= v sin theta

= v cos theta

Question 12

static friction (and equation)

Answer 12

force must be overcome to set an object in motion

Question 13

kinetic friction (and equation)

Answer 13

opposes motion of objects moving relative to each other

Question 14

Newton’s first law

Answer 14

law of inertia - body in a state of motion or at rest will remain in that state unless acted upon by a net force

Question 15

Newton’s second law

Answer 15

when a net force is applied to a body of mass m, the body will be accelerated in the same direction as the force applied to the mass

F=ma (N or kgm/s^2)

Question 16

If a person in a hot air balloon is falling downwards and the F(gravity) > F(drag) then

Answer 16

person is accelerating downward

Question 17

If a person in a hot air balloon is falling downward and the F(gravity) = F(drag) then

Answer 17

person is traveling at constant velocity

Question 18

Newton’s third law

Answer 18

If body A exerts a force on body B, then B will exert a force back onto A that is equal in magnitude, but opposite in direction

Fb = - Fa

Question 19

Newton’s law of gravitation (equation)

Answer 19

all forms of matter experience an attractive force to other forms of matter in the universe

Question 20

mass vs weight

Answer 20

mass - scalar, measures inertia

weight - vector, measures body’s gravitational attraction to the earth (Fg = mg)

Question 21

first condition of equilibrium

Answer 21

an object is in translational equilibrium when the sum of forces pushing it one direction is counterbalanced by the sum of forces acting in the opposite direction

sum F =0

Question 22

Work

Answer 22

constant force acting on an object that moves a displacement of d

W=Fdcos(theta) in Nm

Question 23

For a force perpendicular to displacement, W=?

Answer 23

0

Question 24

For an expanding piston, if W>0

Answer 24

work is done by the system

Question 25

When a piston compresses a gas, W\<0 means

Answer 25

work is done on the system

Question 26

How to determine work from a P vs V curve?

Answer 26

area under the curve

Question 27

power

Answer 27

rate at which work is performed P = W/t in J/s

Question 28

energy is vector/scalar

Answer 28

scalar in J

Question 29

kinetic energy equation

Answer 29

1/2 mv^2

Question 30

Potential energy

Answer 30

energy associated with a body's position, gravitational potential energy due to gravity acting on an object U = mgh

Question 31

Total mechanical energy equation When is it conserved?

Answer 31

E= U + K when sum of kinetic and potential energies remains constant

Question 32

Work-energy theorem

Answer 32

relates work performed by all forces acting on a body in a particular time interval to the change in energy at that time net W = change in energy

Question 33

Conservation of energy

Answer 33

when there are no nonconservative forces (like friction) acting on a system, the total mechanical energy re,ains constant change in E = change in K + change in U = 0

Question 34

linear expansion (mnemonic)

Answer 34

increase in length by most solids when heated when temperature increases, the length of a solid increases "a Lot"

Question 35

volume expansion

Answer 35

increase in volume of fluids with heated

Question 36

conduction convection radiation

Answer 36

direct transfer of energy via molecular collisions transfer of energy by the physical motion of a fluid transfer of energy by electromagnetic waves

Question 37

specific heat (Q)

Answer 37

Q=mc/\T for object does not change phase

Question 38

Q\>0

Answer 38

heat gained

Question 39

Q\<0

Answer 39

heat lost

Question 40

heat of transformation

Answer 40

quantity of heat required to change the phase of 1 g of a substance Q =mL

Question 41

phase changes are ________ processes

Answer 41

isothermal

Question 42

first law of thermodynamics

Answer 42

/\U = Q - W

Question 43

for an adiabatic process, the first law of thermodynamics becomes

Answer 43

/\U=-W

Question 44

for a constant volume process, the first law of thermodynamics becomes

Answer 44

/\U = Q

Question 45

for an isothermal process, the first law of thermodynamics becomes

Answer 45

Q=W

Question 46

second law of thermodynamics

Answer 46

in any thermodynamic process that moves from 1 state of equilibrium to another, the entropy of the system and environment together will either increase or remain unchanged

Question 47

density

Answer 47

m/v in kg/m^3

Question 48

specific gravity

Answer 48

density of substance/density of water

Question 49

density of water

Answer 49

10^3 kg/m^3

Question 50

weight of a fluid

Answer 50

=density\*gV

Question 51

pressure

Answer 51

=F/A in pascals or N/m^2

Question 52

for static fluids of uniform density in a sealed vessel, pressure =

Answer 52

density\*gravity\*z z=depth of the object

Question 53

absolute pressure

Answer 53

in a fluid due to gravity somewhere below the surface P = P(initial) + density\*gz

Question 54

gauge pressure

Answer 54

P(gauge) = P - Patm where P = P(initial) - pgz when P(initial) = Patm then P(gauge) = pgz

Question 55

continuity equation

Answer 55

A1V1 = A2V2

Question 56

bernoulli's equation

Answer 56

P + 1/2 pv^2 + pgh

Question 57

buoyant force equation

Answer 57

Fb = density of fluid \* g\* Vsubmerged

Question 58

archimedes principle

Answer 58

buoyant force is equal to the weight of the displaced fluid. if the weight of the fluid displaced is less than the object's weight, the object will sink if the weight of the fluid displaced is greater than or equal to the object's weight, then it will float

Question 59

Pascal's principle

Answer 59

change in pressure applied to an enclosed fluid is transmitted undiminished to every portion of the fluid and to the walls of the containing vessel

Question 60

coulomb's law

Answer 60

like charges repel and opposite charges attract, with a force proportional to the product of the charges and inversely proportional to the square of the distance between them.

Question 61

electric field

Answer 61

positive point change will move in the same direction as the electric field vector negative charge will move in the opposite direction

Question 62

electrical potential energy

Answer 62

for a charge q at a point in space its the amount of work required to move it from infinity to that point U = q\*/\V = qEd = (kQq)/r in J

Question 63

Electric potential

Answer 63

amount of work required to move a positive test charge q from infinity to a particular point divided by the test charge V=U/q in J/C

Question 64

direction of current

Answer 64

direction that positive charge would flow, from high to low potential

Question 65

ohm's law

Answer 65

V=IR

Question 66

resistance

Answer 66

opposition to the flow of charge

Question 67

when temperature increases, resistance

Answer 67

increases

Question 68

power dissipated by resistors (3 equations)

Answer 68

P=IV=V^2/R=I^2\*R

Question 69

capacitance

Answer 69

ability to store charge per unit voltage C=Q/V