Introductory Physics Homework Help Forum

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Free introductory physics homework help step by step from qualified mentors. Algebra and calculus based general physics homework. High school and undergraduate level.
How to find motional emf w/o an equation for mag field?
  • sequoiasprout
  • · Replies 7 ·
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7
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953
Calculating the voltage across capacitors and resistors with switches
  • radioglava
  • · Replies 2 ·
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2
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1K
Find V-I characteristic for this circuit with ideal diode
  • zenterix
  • · Replies 2 ·
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2
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2K
Purcell Electromagnetism p.301-303: "the longitudinal current I flows, in effect, on the cylinder itself"?
  • Rob2024
  • · Replies 1 ·
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1
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1K
Acceleration of the midpoint of a light rod
  • Bling Fizikst
  • · Replies 3 ·
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3
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1K
Work Done in slowly pulling a thread
  • Bling Fizikst
  • · Replies 28 ·
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28
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Field of contact forces
  • Manish_529
  • · Replies 6 ·
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6
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Determine the Thevenin equivalent circuit
  • zenterix
  • · Replies 2 ·
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2
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Angular Momentum Problem: Mouse walking on a rotating turntable
  • thebeegchung721
  • · Replies 5 ·
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5
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2K
Earthing of two parallel conducting plates
  • palaphys
  • · Replies 11 ·
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11
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Purcell 1.77 Electron jelly
  • Rob2024
  • · Replies 2 ·
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2
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1K
How can voltage between unlike charges decrease with proximity?
  • Brian_D
  • · Replies 4 ·
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4
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Wave interference, "beats" problem
  • Brian_D
  • · Replies 19 ·
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19
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2K
Aerodynamics of a helicopter blade
  • mathisrad
  • · Replies 4 ·
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4
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1K
Which pairs of these diagrams represent equivalent circuits?
  • syllll_213
  • · Replies 4 ·
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4
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I want to know if the sketch I've drawn of the catenary suits the exercise
  • mcastillo356
  • · Replies 11 ·
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11
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2K
Trying to study for my exam but got stuck on exercise
  • Voidness
  • · Replies 7 ·
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7
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1K
Direction and magnitude of electric field produced by current change
  • songoku
  • · Replies 8 ·
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8
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2K
Average battery current in battery charger
  • Antoha1
  • · Replies 7 ·
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7
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2K
Electrostatics: Gauss' Law Problem Finding the Flux through a Conducting Spherical Shell
  • Dev
  • · Replies 9 ·
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9
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2K
Questions about a capacitor with 4 parallel plates
  • palaphys
  • · Replies 14 ·
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14
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2K
Drop of voltage between terminals while conductive rod is rotating
  • Antoha1
  • · Replies 5 ·
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5
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1K
Motion puzzle: Bird flying between a train and a platform
  • anthraxiom
  • · Replies 84 ·
3
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84
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6K
Debugging a Kelvin Water Dropper
  • Silloky
  • · Replies 10 ·
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10
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2K
Electric displacement field density equation
  • lys04
  • · Replies 1 ·
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1
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1K
Calculating of currents in a circuit
  • Antoha1
  • · Replies 2 ·
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2
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994
Force to move a 24 tonne truck one foot in one second
  • Rev. Cheeseman
  • · Replies 10 ·
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10
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2K
Why does the propagation constant in the Helmholtz equation include j?
  • baby_1
  • · Replies 3 ·
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3
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1K
Record Player Physics
  • OutdoorInnovator
  • · Replies 7 ·
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7
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1K
Dielectric boundary value problems
  • lys04
  • · Replies 2 ·
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2
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1K
Polarisation of dielectric materials
  • lys04
  • · Replies 5 ·
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5
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1K
Capacitors, equipotentials, and electric fields
  • palaphys
  • · Replies 5 ·
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5
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2K
How do you calculate the pull of this piston?
  • vdance
  • · Replies 27 ·
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27
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2K
Coin sliding on a table slides across an expanding fabric tape
  • yo yo
  • · Replies 1 ·
Replies
1
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897
Combined tensions of an RLC series circuit with AC current
  • Thai777
  • · Replies 3 ·
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3
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1K
Terminal velocity and acceleration
  • physicals
  • · Replies 7 ·
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7
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1K
Clarifying the Definition Total/Stagnation Pressure (p₀) in Bernoulli'
  • John1704
  • · Replies 2 ·
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2
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1K
A particle's momentum in a magnetic field
  • Antoha1
  • · Replies 3 ·
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3
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1K
The energy needed to construct a charged hollow spherical shell with finite thickness
  • Avital
  • · Replies 1 ·
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1
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1K
Calculation of charge flowing through a loop
  • Antoha1
  • · Replies 7 ·
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7
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1K
Height of the image of my friend on the film
  • syllll_213
  • · Replies 2 ·
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2
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905
Why Was My Answer of 63 cm for the Focal Length of a Converging Lens Incorrect?
  • syllll_213
  • · Replies 1 ·
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1
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855
Drone dragging a hose behind it
  • ethanesh
  • · Replies 24 ·
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24
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2K
Torque biomechanics
  • Naucus
  • · Replies 6 ·
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6
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2K
(Answer check) for a work problem
  • helloword365
  • · Replies 3 ·
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3
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905
Question related two different ways to do solution
  • helloword365
  • · Replies 1 ·
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1
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826
CO2-powered metric racer car competition | help please?
  • sophiasxxn_134
  • · Replies 14 ·
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14
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2K
Force acting on one side of a fluid
  • palaphys
  • · Replies 22 ·
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22
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2K
Coefficient of Restitution for a Hypothetical Collision where masses are not equal after the collision compared to before the collision
  • rdemyan
  • · Replies 6 ·
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6
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1K
Confusion regarding surface tension direction and force balance
  • palaphys
  • · Replies 39 ·
2
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39
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3K
Convert to Center of Mass Reference Frame
  • rdemyan
  • · Replies 9 ·
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9
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How far from the point of release will the ball hit the ground?
  • Mohammad Ishmas
  • · Replies 16 ·
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16
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Irodov 1.23 confusion: Calculate distance traveled and time elapsed for this decelerating particle
  • anthraxiom
  • · Replies 2 ·
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2
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2K
What is force? How can we interpret the full definition of force?
  • wondu12345ABCD
  • · Replies 6 ·
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6
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Calculate velocities in COM reference frame for 2D collision
  • rdemyan
  • · Replies 27 ·
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27
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Inclined plane problem
  • Vidrinho
  • · Replies 13 ·
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13
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AP physics 2: Phase change in thin film interference
  • AAONA
  • · Replies 1 ·
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1
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1K
Calculate the speed and angle of the center of mass before a collision
  • rdemyan
  • · Replies 3 ·
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3
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1K
Mastering physics homework: Mass oscillating on a vertical spring
  • BadAtPhysic
  • · Replies 2 ·
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2
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924
Friction direction change in a inclined circular bend (car on a road)
  • pgirl1729
  • · Replies 11 ·
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11
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2K
Induced current and force on circular loop in varying magnetic field
  • songoku
  • · Replies 4 ·
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4
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Problem on Radiation Pressure
  • Mohammad Ishmas
  • · Replies 33 ·
2
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33
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2K
Quick Physics Questions I found online and need explanations solving
  • Candice123
  • · Replies 10 ·
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10
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1K
Calculate the energy transferred given the voltage, current and time
  • GARV ARORA
  • · Replies 5 ·
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5
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983
This 3 mass atwood problem is confusing me
  • Thai777
  • · Replies 4 ·
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4
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2K
Left-to-Right Wave — How Does Particle X Move?
  • Physical_Fire
  • · Replies 23 ·
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23
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2K
Computing the moment of inertia for a rotary inverted pendulum
  • Remusco
  • · Replies 5 ·
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5
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1K
Ball on a string thrown around a spool
  • kekpillangok
  • · Replies 3 ·
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3
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1K
Network Analysis, Kirchhoff's Laws, changing current source to voltage
  • Emo_Jesus
  • · Replies 4 ·
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4
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2K
Graphs of RC Circuit Responses
  • stunner5000pt
  • · Replies 3 ·
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3
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1K
The problem of one tube and two balls on a plane
  • crazy lee
  • · Replies 60 ·
3
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60
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4K
Calculating the Forces on a Charge
  • GodlessStar
  • · Replies 7 ·
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7
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1K
Ambiguous Problem Statement on Determining Speed of Aircraft
  • vcsharp2003
  • · Replies 13 ·
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13
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2K
How does a transistor act as an amplifier?
  • Aurelius120
  • · Replies 6 ·
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6
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1K
How do I find the intersection of the wrench's LOA?
  • daisy7777
  • · Replies 4 ·
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4
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1K
Momentum: why don't the two carts become one?
  • paulb203
  • · Replies 32 ·
2
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32
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2K
How to calculate the errors in the measured period of a pendulum?
  • Lotto
  • · Replies 6 ·
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6
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1K
Series and Parallel Circuits using symmetry
  • psandadi
  • · Replies 10 ·
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10
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How is the slider connected to the switch?
  • Physical_Fire
  • · Replies 6 ·
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6
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1K
Thermal expansion of a glass rod and a metal ruler
  • Brightly
  • · Replies 8 ·
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8
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1K
A problem from a physics national competition
  • Jim Alexandridis
  • · Replies 13 ·
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13
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2K
Change in entropy of the surroundings in an irreversible process
  • palaphys
  • · Replies 14 ·
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14
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2K
Surface current of superconducting sphere in magnetic field
  • Jan05
  • · Replies 1 ·
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1
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1K
Force of car pushing on a truck
  • syllll_213
  • · Replies 25 ·
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25
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2K
Force needed to raise a backpack
  • syllll_213
  • · Replies 1 ·
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1
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984
Uniform circular motion angle relationship
  • syllll_213
  • · Replies 6 ·
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6
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893
Simulating a Rotary Inverted Pendulum in Python
  • Remusco
  • · Replies 15 ·
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15
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3K
Pressure of water coming out of a hose nozzle
  • mr_sparxx
  • · Replies 7 ·
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7
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2K
Focal length of the eyepiece lens in a compound microscope
  • tellmesomething
  • · Replies 7 ·
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7
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2K
Find the magnitude of the child's acceleration
  • chwala
  • · Replies 7 ·
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7
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2K
Why are these forces not included in the solution? (Torque Problem)
  • mathandphysics
  • · Replies 12 ·
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12
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1K
Why do compasses always point in the wrong direction?
  • ulrichburke
  • · Replies 6 ·
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6
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2K
Charge on disk with non uniform surface charge density
  • songoku
  • · Replies 12 ·
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12
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2K
Optics problem with a glass lens immersed in water
  • tellmesomething
  • · Replies 3 ·
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3
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1K
Homework: Can a rest frame be chosen for the center of momentum for a system of two photons?
  • sHimprinten
  • · Replies 7 ·
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7
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1K
1-dimensional kinematics - final velocity of 2 trains in opposing direction
  • syllll_213
  • · Replies 3 ·
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3
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1K
Total energy of a wave on a string
  • Brian_D
  • · Replies 2 ·
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2
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1K
What happens to the position of two attracting charges when a conductor is inserted between them?
  • Rob2024
  • · Replies 4 ·
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4
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1K
Spring force required to overcome friction between two blocks
  • MenchiKatsu
  • · Replies 10 ·
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10
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1K
Rolling without slipping problem
  • cianfa72
  • · Replies 42 ·
2
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42
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5K