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1
Q

Whats the unit?

Lenght

A

meter (m)

2
Q

Whats the unit?

Mass

A

Kg

3
Q

Whats the unit?

Force

A

N

4
Q

Whats the unit?

Time

A

s

5
Q

Whats the unit?

Work and Energy

A

J

6
Q

Whats the unit?

Power

A

W

7
Q

Give the prefix and abbreviation for each of the following powers:
10^9

A

Giga (G)

8
Q

Give the prefix and abbreviation for each of the following powers:
10^6

A

Mega (M)

9
Q

Give the prefix and abbreviation for each of the following powers:
10^3

A

Kilo (K)

10
Q

Give the prefix and abbreviation for each of the following powers:
10^-2

A

Centi (c)

11
Q

Give the prefix and abbreviation for each of the following powers:
10^-3

A

Milli (m)

12
Q

Give the prefix and abbreviation for each of the following powers:
10^-6

A

Micro (µ)

13
Q

Give the prefix and abbreviation for each of the following powers:
10^-9

A

Nano (n)

14
Q

Give the prefix and abbreviation for each of the following powers:
10^-12

A

Pico (p)

15
Q

what are the sin and cos values for the following angles?

0

A

sin: 0
cos: 1

16
Q

what are the sin and cos values for the following angles?

90

A

sin: 1
cos: 0

17
Q

what are the sin and cos values for the following angles?

30

A

sin: 1/2
cos: √3/2

18
Q

what are the sin and cos values for the following angles?

60

A

sin: √3/2
cos: 1/2

19
Q

what are the sin and cos values for the following angles?

45

A

sin: √2/2
cos: √2/2

20
Q

what are the sin and cos values for the following angles?

180

A

sin: 0
cos: -1

21
Q

what is the difference between a scalar quantity and a vector quality?

A

Scalar: magnitude but no direction
Vector: magnitude and direction

22
Q

Scalar or vector?

Distance, speed and mass

A

scalars

23
Q

Scalar or vector?

Displacement, Velocity and force

A

vectors

24
Q

(T/F) The sum of two vectors is the resultant of the vectors

A

True

25
Q

Formula:

Average acceleration

A

a= ∆v/∆t

26
Q

Formula:

v=

A

V= Vo +at

27
Q

Formula:

∆x=

A

∆z= Vot+ (at^2/2)= Vt= (Vo + v / 2)t

28
Q

Formula:

V^2

A

V^2= Vo^2 +2a (X-Xo)

29
Q

Formula:

V=

A

V= (Vo + v / 2)

30
Q

Is weight a vector or scalar?

What is the formula for calculating weight?

A

vector

weight= mass x gravity

31
Q

What are the Newton’s three laws of motion?

A
  1. A body in motion with constant velocity in a straight line path or at rest will remain that way unless an net force acts upon it.
  2. F=ma
  3. To every force there is always an equal and opposite force.
32
Q

What are the formulas for the initial horizontal and vertical velocities of a projectile launched with speed v at and angle of ∅ to the horizontal?

A

horizontal: Vcos∅
Vertical: Vsin∅

33
Q

what does the total horizontal distance,x, traveled by a projectile equal?

A

X= (initial horizontal velocity)(time in the air)

34
Q

What is the formula for gravitational force? F=

A

F= G m1m2 / r^2

35
Q

If the distance between two objects is doubled, by how much is the force of gravity increased or decreased?

A

decrease by a factor of 4

36
Q

(T/F) A body in translational equilibrium has a net force moving it at a constant velocity.

A

False.

A body in translational equilibrium has no net force acting on it.

37
Q

If a lever arm is halved, by how much does the torque increase or decrease?

A

decrease by half

38
Q

what is the formula for torque?

A

T= r F sin ∅ (r: distance between force and axis rotation)

39
Q

when calculating torque, which rotation direction is considered positive and which negative?

A

counterclock: +
clockwise: -

40
Q

(T/F) For rotational equilibrium to occur, the sum of all torques acting on a body must be zero.

A

True

41
Q

what is translational motion?

A

motion in which the position of the object’s center of mass changes as a function of time.

42
Q

what is the formula for the force of static friction?

A

Fs ≤ µs N

43
Q

what is the formula for the force of kinetic friction?

A

Fk = µk N

44
Q

what is the formula for centripetal acceleration (for a body in uniform circular motion)? a=

A

a= (velocity)^2 / radius = v^2/r

45
Q

(T/F) For a planet orbiting a star, the centripetal force is equal to the gravitational force.

A

true

46
Q

what is the formula for work?

A

W= F d cos ∅

47
Q

what is the unit of work?

A

Joule (N*m)

48
Q

what is the formula for power?

A

P= W/t

49
Q

what is the unit of power?

A

Watt (1 J/sec)

50
Q

what are the units for KE?

A

Joules

51
Q

What is the formula for gravitational potential energy? U=

A

U=mgh

52
Q

what are the units of gravitational potential energy?

A

Joules

53
Q

(T/F) The total mechanical energy of a body is the sum of its kinetic energy and potential energies.

A

True

54
Q

Is the total mechanical energy a constant if the only forces that act on a body are conservative (E=K+U=Constant)

A

Yes

55
Q

What is the change in energy of a system if only conservative forces act upon it?

A

If only conservative forces act on a body, then ∆E=0

56
Q

What is the formula for momentum? p=

A

P=mv

57
Q

what is the formula for impulse J? J=

A

J= Ft= MV-MVo=∆P

58
Q

Is kinetic energy conserved in a completely elastic collision?

A

yes

59
Q

(T/F) Net external force must be equal zero for conservation of momentum to occur.

A

true

60
Q

What is the formula for the center of mass for two masses, m1 and m2, lying along the x-axis at points x1 and x2?

A

X= (m1x1 + m2x2) / (m1+m2)

61
Q

(T/F) Momentum is not conserved in an inelastic collision.

A

False

62
Q

What are the temperatures in Kelvin and Celsius for the following?
Absolute Zero.

A

0 K

-273 C

63
Q

What are the temperatures in Kelvin and Celsius for the following?
Freezing point of water

A

273 K

0 C

64
Q

What are the temperatures in Kelvin and Celsius for the following?
Boiling point of water

A

373 K

100 C

65
Q

What is the formula for converting Kelvin to Celsius?

A

Tc= Tk-273

66
Q

What is the formula for thermal expansion of a solid?

A

∆L=α L∆T

67
Q

What is the formula for volume thermal expansion of a liquid or a solid?

A

∆V= ɞV∆T

68
Q

What type of heat transfer involves the direct transfer of energy from molecule to molecule through molecular collisions?

A

Conduction

69
Q

What type of heat transfer involves the transfer of energy by electromagnetic waves?

A

Radiation

70
Q

What type of heat transfer involves the physical motion of heated material?

A

Convection.

71
Q

what are the units of heat?

A

calorie, btu or Joule.

72
Q

what is the difference between a calorie and Calorie?

A

Calorie is a nutritional term = 1000 calories

73
Q

What is the formula relating heat gained and temp charge? Q=

A

Q=mc∆T

74
Q

what is heat of fusion?

A

amount of energy required for a phase from solid to liquid

75
Q

what is heat vaporization?

A

Heat vaporization is the amount of energy required for a phase change from liquid to gas

76
Q

What is the formula for heat gained or lost during a phase change?

A

Q= mL

77
Q

What is the SI unit of pressure?

A

Pascal

78
Q

What is an isobaric process?

A

process done @ constant pressure

79
Q

What is the formula for work (given an isobaric process?

A

W=P∆V

80
Q

What is the formula for the first law of thermodynamics?

A

∆U= Heat energy gained- Work done by the system

81
Q

(T/F) Heat flow out of system is (+) and heat flow into a system is (-)

A

False.
heat out system -
heat into system +

82
Q

What is an adiabatic process?

A

one in which no heat flows from the system to its surroundings or vice versa

83
Q

What is the second law of thermodynamics?

A

entropy of a closed system will either increase or remain unchanged.

84
Q

Does a totally reversible process increase the entropy if the universe? what about an irreversible process?

A

totally reversible: does not increase entropy of the universe but an irreversible process does.

85
Q

What is the equation for density?

A

p=m/v

86
Q

What is the density of H2O?

A

1000kg/m^3 = 1g/cm^3

87
Q

What is specific gravity?

A

ratio of a substances density to the density of water.

88
Q

What is the formula for calculating pressure?

A

P= Force/Area

89
Q

What is the formula for absolute pressure in a liquid?

A

P= Surface pressure + (p)(gravity)(depth)

= Po+ pgh

90
Q

What is gauge pressure?

A

pressure in excess at atmospheric pressure

91
Q

(T/F) Pascal’s principle states that a change in pressure applied to an enclosed fluid is transmitted undiminished to every portion of the fluid and to the walls of the container.

A

True

92
Q

What is the relationship between the areas and forces when the system is in equilibrium?

A

(F1/A1)=(F2/A2)

93
Q

(T/F) Both pistons move the same distance when a force is applied to one of them.

A

False

94
Q

What is the formula for buoyant force?

A

FB=pgV

95
Q

Given a pipe varying cross sections, how do fluid velocity and cross-sectional area relate throughout the pipe?

A

A1V1=A2V2

96
Q

what is viscosity?

A

measure of the internal friction of a fluid.

97
Q

Does viscosity of a liquid generally increase or decrease as temp rises?

A

an increase in temp generally causes the viscosity of a liquid to decrease.

98
Q

What is the formula for Young’s Modulus?

A

Y= (F/A) / (∆L/L)

99
Q

(T/F) Unlike charge attract and like charges repel.

A

True

100
Q

What is the formula for Coulomb’s Law?

A

F= (Constant)(charge 1)(charge 2)/ distance^2

101
Q

If the distance between two charged objects is tripled, by how much does the electrostatic force change?

A

decrease by factor of 9

102
Q

If the distance between two charged objects is halved, by how much does the electrostatic force change?

A

increase by a factor of 4

103
Q

What is the formula for an electric field at a distance(r) from a charge (q)?

A

E=K (q)/r^2

104
Q

In which direction will an electric field vector point around a positive charge?

A

away

105
Q

In which direction will an electric field vector point around a negative charge?

A

toward

106
Q

What is the formula for the force that a charge (q) experiences in an electric field (E)?

A

F=qE

107
Q

what are the units of an electric field?

A

(Newtons/Coulomb) or (Volts/meter)

108
Q

what are the units of voltage?

A

Volts or Joules/Coulomb

109
Q

what is the formula for electric potential given a charge (q) at a distance of (r)?

A

V=k (q/r)

110
Q

What is the potential difference between two points on an equipotential line?

A

0

111
Q

what is the formula for electrical potential energy?

A

U= qV

112
Q

How much work is done on a charge if it is moved in a straight path between two equipotential points?

A

no net work is done.

113
Q

what are the units of magnetic field?

A

Tesla.

Tesla = 10^4 Gauss

114
Q

what is the formula for the force on a moving charged particle in a magnetic field?

A

F= qvBsin ∅

115
Q

What force will a stationary charged particle in a magnetic field experience?

A

no force

116
Q

What force will a moving charge experience if it travels parallel or antiparallel to a magnetic field?

A

no force

117
Q

What are the units of current?

A

Amperes

1A= 1 Coulomb/sec

118
Q

What is the formula for current?

A

I=∆q/∆t

119
Q

What is the formula for the force on a current carrying wire in the presence of a magnetic field?

A

F= ILB sin ∅

120
Q

A proton moving in a magnetic field experiences a force towards the top of the page. An electron moving in the same direction as the proton experiences a force in which direction?

A

Towards the bottom of the page

121
Q

A proton moves towards the top of the page in a region where a magnetic field is directed into the page. What is the direction of the magnetic force?

A

Towards the left

122
Q

A long straight wire carries a current directed towards the top of the page. What is the direction of the magnetic field on the left side of the wire?

A

The field points out of the page.

123
Q

What is the formula for the magnetic field created by a long straight wire?

A

B= µo i/ 2 π r

124
Q

A magnetic field is created by a loop of wire. What is the formula for the magnetic field at the center of the loop?

A

B= µo i/ 2r

125
Q

(T/F) in DC current, the charge flows in one direction only.

A

True

126
Q

(T/F) In AC current, the change flows in one direction only.

A

False.

The flow of charge changes direction periodically.

127
Q

(T/F) By convention, the direction of current is the direction in which a negative change would flow.

A

False.

Direction of current is where the positive charge would flow.

128
Q

What is the formula for Ohm’s law?

A

V=IR

129
Q

How do the following affect the resistance of a conductor?

Increased length

A

as the length increases, the resistance increases.

130
Q

How do the following affect the resistance of a conductor?

Increased cross-sectional area.

A

Cross-sectional area increases= resistance decreases.

131
Q

How do the following affect the resistance of a conductor?

Increased temperature

A

Temp increase= resistance usually increases

132
Q
How do the following affect the resistance of a conductor?
Increase resistivity (ρ)
A

resistivity increases= resistance increases.

133
Q

What is the formula for electrical power?

A

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

134
Q

What is the formula for calculating resistance given resistors in series?

A

Rs= R1 +R2..etc

135
Q

What is the formula for calculating resistance given resistors in parallel?

A

1/Rp= 1/R1 +1/R2…etc

136
Q

What is Kirchoff’s 2nd law?

A

The sum of the voltage drops around a circuit loop equals the sum of the voltage rises around the loop.

137
Q

If a 7A of current flow into a three way junction and 3A leave via one of the routes, how much current leaves via the other?

A

7A- 3A = 4A

138
Q

What is the formula for capacitance?

A

C=Q/V

139
Q

What are the units of capacitance?

A

1 Farad = 1 Coulomb/Voltage

140
Q

What is the formula for the electric field between the plates of a capacitor?

A

E= V/d

141
Q

(T/F) As plate area increases, capacitance increases proportionally.

A

True

142
Q

Does the introduction of a dielectric material between the plates of a capacitor increase or decrease the capacitance?

A

increases the capacitance.

143
Q

What is the formula for calculating capacitance given capacitors in series?

A

1/Cs= 1/C1+ 1/C2…etc

144
Q

What is the formula for calculating capacitance given capacitors in parallel?

A

Cp= C1+ C2..etc

145
Q

For AC current, what us the formula for calculating Irms?

A

Irms= Imax/ √2

146
Q

For AC current, what is the formula for calculating Vrms?

A

Vrms= Vmax/ √2

147
Q

What is the formula for Hooke’s law?

A

F= -K x

148
Q

What are the formulas for angular frequencies of a mass on a spring and of a pendulum (SHM)?

A
ω= √K/m [spring]
ω= √g/L [pendulum]
149
Q

What is the formula for kinetic energy (SHM)?

A

K= (1/2) mv^2

150
Q

What is the formula for potential energy (SHM)?

A

U=(1/2)kx^2 [ spring]

U= mgh [pendulum]

151
Q

(T/F) For an object in SHM, E=K+U= Constant.

A

True

152
Q

When is an object’s kinetic energy greatest (SHM)?

A

at equilibrium point.

153
Q

When is an object’s potential energy greatest (SHM)?

A

at maximum displacement from equilibrium

154
Q

(T/F) For an object in SHM, frequency = 1/Period.

A

True

155
Q

What are the formulas for the period of a mass on a spring and of a pendulum in SHM?

A
T= 2Π√m/k [spring]
T= 2Π√L/g [pendulum]
156
Q

Describe particle oscillation in a transverse wave.

A

particles oscillate perpendicular to wave motion in a transverse wave.

157
Q

Describe particle oscillation in a longitudinal wave.

A

Particles oscillate along the direction of wave motion in a longitudinal wave.

158
Q

What is the formula relating the speed of a wave to its frequency (f) and wavelength (λ)?

A

v=fλ

159
Q

(T/F) A sinusoidal wave crosses its equilibrium point every 90°

A

False.

a sinusoidal wave crosses its equilibrium point every 180 °

160
Q

(T/F) The fundamental harmonic has the longest wavelength and thus the smallest frequency of all the harmonics.

A

True

161
Q

(T/F) The higher the harmonic, the greater the wavelength.

A

False.

The higher the harmonic= the shorter the wavelength

162
Q

What is a node?

A

point in a standing wave that remains at rest.

163
Q

What is an antinode?

A

point in a standing wave that fluctuates at max amplitude.

164
Q

Two waves that are 180° out of phase exhibit which type f interference?

A

Destructive

165
Q

Two waves that are 720° out of phase exhibit which type f interference?

A

Constructive

166
Q

(T/F) When two waves are out of phase by 180° and interfere with each other, the resulting displacement is always zero.

A

False.

The resultant displacement is only zero when the two waves have equal amplitudes.

167
Q

What is the formula for intensity?

A

I=(P/A)

I= (power/ area)

168
Q

What is the beat frequency for two frequencies which differ by 4 Hz?

A

4Hz.

The beat frequency is equal to the difference of the two frequencies.

169
Q

(T/F) The observed frequency from a source emitting a sound is higher if the source is moving toward a stationary observer.

A

True

170
Q

(T/F) Standing waves in pipes open at both ends have nodes at the ends of the pipes.

A

False.

standing waves in pipes open at both ends have antinodes at the ends of the pipe.

171
Q

(T/F) Standing waves in strings fixed at both ends have nodes at the ends of the strings.

A

true

172
Q

(T/F) Higher harmonics of standing waves in open pipes have higher wave speed than lower harmonics.

A

False. The wave speed of all harmonics is the same.

173
Q

What is the speed of an electromagnetic wave (light) in a vacuum?

A

3x 10 ^8 m/s

174
Q

What type of image do plane mirrors create (real or virtual)?

A

virtual

175
Q

How are focal length and radius of curvature related?

A

Focal length = radius of curvature /2 = r/2

176
Q

What is the formula relating object distance, image distance and focal length?

A

1/f= 1/o+1/i=2/r

177
Q

Does a virtual image have a positive or negative image distance?

A

negative

178
Q

If an image is in front of a mirror, is it real or virtual?

A

real

179
Q

Does a real image have a positive or negative image distance?

A

positive

180
Q

whats the formula for magnification?

A

m=-i/o

181
Q

(T/F) A negative magnification signifies an upright image.

A

False.
A negative magnification signifies an inverted image
A positive magnification signifies an upright image.

182
Q

What type of image does a diverging (convex) mirror create?

A

A diverging mirror always creates a virtual upright image.

183
Q

What type of image does a converging (concave) mirror create when the object is placed beyond the focal point?

A

real inverted image

184
Q

What type of image does a converging (concave) mirror create when the object is placed inside the focal point?

A

virtual upright image

185
Q

Does a convex mirror have a positive or negative focal length (or radius of curvature)?

A

negative

186
Q

Does a concave mirror have a positive or negative focal length ( or radius of curvature)?

A

positive

187
Q

What is the formula for index of refraction?

A

n= c/v

188
Q

What is the formula for snell’s law?

A

n1 sin θ1 = n2 sin θ2

189
Q

Under what conditions will light undergo total internal reflection?

A

internal reflection will occur when light travels from a medium with a higher index of refraction to a medium with a lower index of refraction and with an angle of incidence greater than the critical angle.

190
Q

Does a converging lens have a positive or negative focal length?

A

positive

191
Q

Does a diverging lens have a positive or negative focal length?

A

negative

192
Q

(T/F) The “real” side of a lens is the side opposite that from which light originates

A

true

193
Q

What type of image does a diverging lens produce?

A

virtual upright

194
Q

(T/F) The electron Volt (eV) is a unit of energy.

A

True

195
Q

What happens to an electron that absorbs a photon?

A

jump to higher energy level

196
Q

what happens when an electron jumps from a higher energy level to a lower energy level (orbit)?

A

will emit a photon whose energy equals to the difference in energy between the two levels.

197
Q

What is the minimum energy needed to ionize an electron in a state with energy -10 eV?

A

10 eV.

198
Q

What is the threshold frequency (photoelectric effect)?

A

minimum frequency of light that will cause the emissions an electron.

199
Q

(T/F) The excess energy of a photon is converted to extra kinetic energy of the emitted electron

A

true

200
Q

What is the formula for calculating the kinetic energy of an emitted electron?

A

K- hf-W
W= h x fT
fT: threshold frequency

201
Q

How many electrons will be emitted when using light with a frequency below the threshold frequency?

A

None.

202
Q

Is the energy of a photon dependent on frequency or on amplitude?

A

frequency

203
Q

What is the formula for calculating the energy of a photon?

A

E=hf

204
Q

What is the photoelectric effect?

A

phenomenon whereby electrons are emitted by a metal that is exposed to light

205
Q

(T/F) Photon energy increases when wavelength increases.

A

False.

Photon energy increases as wavelength increases.

206
Q

(T/F) The splitting of white light in a prism is an example of dispersion.

A

True

207
Q

What is diffraction?

A

spreading out of light as t passes through a narrow opening.

208
Q

(T/F) Light waves can constructively and/or destructively interfere with each other.

A

True

209
Q

What is polarized light?

A

light in which the electric fields of all the waves are oriented in the same direction.

210
Q

what type of image does a converging (convex) lens create when the object is placed beyond the focal point?

A

real inverted

211
Q

what type of image does a converging (convex) lens create when the object is placed inside the focal point?

A

virtual upright

212
Q

What re the units of power for a lens?

A

diopters

213
Q

What is the formula for calculating lens power?

A

P=1/f