Introductory Physics Homework Help Forum

Free introductory physics homework help step by step from qualified mentors. Algebra and calculus based general physics homework. High school and undergraduate level.

Threads

Proving the Second Partials Test

  • mattmns
  • · Replies 2 ·
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2

Simplifying (▲^2 - x▲)(x^3) Using Finite Differences

  • irony of truth
  • · Replies 2 ·
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2

Why Is My Calculation Using the Gas Law Equation Incorrect?

  • pippermay
  • · Replies 2 ·
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2

Kinematics od deccelerating train

  • frozen7
  • · Replies 15 ·
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15

Launching an airoplane using a mouse trap

  • gangsta_jme4
  • · Replies 18 ·
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18

Finding the tangential speed Help

  • Ester
  • · Replies 2 ·
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2

Misconceptions about length contraction

  • delton
  • · Replies 6 ·
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6

EM Induction: Increasing Turns, Increasing EMF, Current?

  • phyphysics
  • · Replies 2 ·
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2

Does Every Closed Form on U Being Exact Imply the Same for f(U)?

  • rocket
  • · Replies 2 ·
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2

Marriage Problem Every Man & Woman Friends w/ r People

  • Pietjuh
  • · Replies 4 ·
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4

Solving E-Fields using Gauss' Law: Choosing Surfaces

  • misogynisticfeminist
  • · Replies 2 ·
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2

Convergence of Improper Integral

  • pbialos
  • · Replies 5 ·
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5

Electron Negativity: Why Electrons Have a Negative Charge

  • juskovin
  • · Replies 2 ·
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2
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2

How is sigma subscript (y) related to spin and magnetic moment?

  • danai_pa
  • · Replies 2 ·
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2

Finding the wavelength (new to physics)

  • StotleD
  • · Replies 2 ·
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2

Uniform Hoop Hit By a Small Sticky Ball of Putty

  • SpeeDFX
  • · Replies 7 ·
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7

My great Confusion in Physics Derivations.Help

  • Aladin
  • · Replies 5 ·
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5

How Do You Derive the Volume of an n-Dimensional Sphere?

  • rocket
  • · Replies 2 ·
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2

Help with Paradoxical Groups: Vectors, Finite Groups, F3 & Z

  • JSG31883
  • · Replies 3 ·
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3

Trying to understand microfluiditics [sp, microfluidics]

  • sr6622
  • · Replies 5 ·
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5

Static Friction of a washing machine

  • brayrbob
  • · Replies 8 ·
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8

Volume of n-dimensional sphere

  • rocket
  • · Replies 2 ·
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2

Diffraction by single slit - effect of increasing the slit width

  • physicsilliterate
  • · Replies 2 ·
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2

Derivation of solid sphere moment of inertia

  • jordanl122
  • · Replies 10 ·
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10

Creating a Physics Toy: Tips, Examples, and Resources for Graduation

  • rouvin
  • · Replies 2 ·
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2

What is the Vector Identity for \vec A and \hat n?

  • Reshma
  • · Replies 2 ·
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2

Wavelength & Frequency: No Change

  • primarygun
  • · Replies 4 ·
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4

Carnot Cycle and Adiabatic process

  • Bob19
  • · Replies 15 ·
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15

Sum of Series w/ 2's & 3's: Find the Total

  • iNCREDiBLE
  • · Replies 16 ·
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16

Lenses/Mirrors, [1/f = (1/do+1/di)] sign help

  • michaelw
  • · Replies 7 ·
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7

What does the y-intercept represent in Kepler's 3rd law relationship?

  • patcho
  • · Replies 2 ·
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2

Polarization I = Io*cos^2 theta

  • DAP1MP13
  • · Replies 4 ·
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4

Solving the Kinetic Friction Problem - Bob's Dilemma

  • brayrbob
  • · Replies 4 ·
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4

Find Tension in Motion of 2 Wires & Sphere in Circle

  • psingh
  • · Replies 9 ·
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9

Car travels with fwd force help

  • aliciaw0
  • · Replies 9 ·
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9

Finding Focal Lengths of Microscope Lenses

  • shorty_47_2000
  • · Replies 3 ·
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3

Equilateral triangle electrostatics problem

  • in10sivkid
  • · Replies 10 ·
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10

2 Balls on inclined plane problem

  • Bama
  • · Replies 5 ·
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5

How Far Can a Painter Safely Walk on an Overhanging Plank Before It Tips?

  • rlmurra2
  • · Replies 14 ·
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14

Sequences of positive numbers and limits

  • iNCREDiBLE
  • · Replies 2 ·
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2

Calculating Total Translational Kinetic Energy in an E.Coli Bacterium

  • Phoenix314
  • · Replies 6 ·
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6

How Thick Is the Glass Plate Based on Visibility Circle?

  • ERB225
  • · Replies 2 ·
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2

How Can a 3D PDE Be Simplified to a 1D Equation in Theta?

  • Ido
  • · Replies 2 ·
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2

Expressing velocity as a function of the distance (not time elapsed)

  • Beez
  • · Replies 3 ·
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3

Question about computing torque?

  • pmfinnegan2
  • · Replies 2 ·
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2

Is this well-defined in the rational numbers

  • iNCREDiBLE
  • · Replies 6 ·
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6

Dynamics coefficient of friction

  • polly06
  • · Replies 5 ·
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5

Magnetic Field and Induced Currents in Rails Problem

  • phyphysics
  • · Replies 10 ·
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10

Calculating Orbits of Groups: SO(3)

  • rdc30ynow
  • · Replies 2 ·
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2

Solving Diff. Equations: Population Growth & Changes

  • gordda
  • · Replies 6 ·
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6

Hwk Problem about Convex Mirrors

  • shawonna23
  • · Replies 2 ·
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2

Why Is the Number e Considered Irrational?

  • VietDao29
  • · Replies 5 ·
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5

Faraday's law of electomagnetic induction

  • mayo2kett
  • · Replies 5 ·
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5

Physics B vs. Physics C, Calculus AB vs. Calculus BC

  • mewhoexactlywhat
  • · Replies 10 ·
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10

Is the Equation for Refractive Index Accurate?

  • primarygun
  • · Replies 13 ·
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13

Related rates of change (2 problems)

  • Pseudo Statistic
  • · Replies 8 ·
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8

Deriving the Fresnel Equations for E Field in Plane of Incidence

  • Cummings
  • · Replies 2 ·
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2

How Do You Calculate the Peak EMF of a Rotating Coil in a Magnetic Field?

  • mayo2kett
  • · Replies 3 ·
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3

Give the range of possible solutons of trig equation

  • plucker_08
  • · Replies 3 ·
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3

Geometry: I want to understand some points

  • irony of truth
  • · Replies 5 ·
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5

Finding mag E of 2 thin-walled concentric cylindrical shells

  • mr_coffee
  • · Replies 10 ·
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10

Instantaneous Energy Density: 501 N/C

  • hotstuff
  • · Replies 2 ·
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2

Time velocity accelertion @ point x two electrons

  • rebeka
  • · Replies 4 ·
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4

Finding speed using conservation of mechanical energy

  • Ester
  • · Replies 2 ·
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2

What's the Difference Between 'Out of Paper' and 'Upwards' in Magnetic Forces?

  • phyphysics
  • · Replies 10 ·
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10

Proof of Coulomb's Law using Gauss' Law

  • jdstokes
  • · Replies 2 ·
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2

Series Capacitance: C1, C2 at 1000V - Calc Total, Charge & PD

  • in10sivkid
  • · Replies 4 ·
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4

Time as a function of distance? electrostatic force

  • rebeka
  • · Replies 16 ·
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16

Compute the electric field in air

  • in10sivkid
  • · Replies 4 ·
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4

Uncertainty Relations and Functions of Operators

  • Dathascome
  • · Replies 5 ·
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5

Finding the charge of a drum, i got the steps i think

  • mr_coffee
  • · Replies 8 ·
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8

Find Midpoint of Shaped Area: 300, 5000, 1500, 5142

  • iNCREDiBLE
  • · Replies 2 ·
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2

Satelite how far from center of earth?

  • ChinToka
  • · Replies 2 ·
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2

How to Solve a Tricky Differential Equation: A Textbook Example

  • asdf1
  • · Replies 9 ·
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9

Calculating Wavelength without distance

  • StotleD
  • · Replies 3 ·
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3

What Is the Minimum Tension Needed to Move a Toaster on a Countertop?

  • rlmurra2
  • · Replies 14 ·
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14

Questions about Fleming's left hand rule

  • phyphysics
  • · Replies 2 ·
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2
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3

What is the gravitational force on the satellite?

  • badman
  • · Replies 8 ·
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8

"Find the Current in a 25mH Inductor Circuit

  • hotstuff
  • · Replies 2 ·
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2
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4

Asking about direction of magnetic force

  • phyphysics
  • · Replies 4 ·
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4

Ummm, what do these equations do

  • physics noob
  • · Replies 3 ·
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3

Plotting Direction Fields for Differential Equations: A Mathematica Tutorial

  • DivGradCurl
  • · Replies 5 ·
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5

How Much Weight Must a Balloon Drop to Rise Quickly?

  • aud11888
  • · Replies 8 ·
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8
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5

Conservation of energy of sliding block

  • orionics
  • · Replies 4 ·
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4

Struggling with yet another DE problem -_-

  • Benny
  • · Replies 2 ·
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2

Solving Low T, High B Behavior of (deltaE)^2 = C*[sinh(a*B)]^-2

  • Allday
  • · Replies 6 ·
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6

Calculating Torque & Lever Arm for a Lunch Tray

  • drewfus
  • · Replies 3 ·
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3

Solve Function Problem: Steps Explained & Book Recommendation

  • asdf1
  • · Replies 6 ·
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6

Is Calculus a Smooth Transition After Mastering Trig and Algebra 2?

  • Brady
  • · Replies 3 ·
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3

P - What books are recommended for the U.S. Physics Olympiad?

  • sr6622
  • · Replies 2 ·
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2

Where Did I Go Wrong in Finding the Net Charge on a Sphere?

  • mr_coffee
  • · Replies 2 ·
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2

Magnitude of the net force that acts on the charge

  • Confused5283
  • · Replies 2 ·
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2

What is the frequency for a period of 60 microseconds?

  • taho2720
  • · Replies 2 ·
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2

Tension HW: Change in Coupling Bars A, B, C with 39 kg Removed

  • TikiPost10
  • · Replies 2 ·
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2

Solving Potential Diff. on Capacitors Series Connection w/300V

  • Hyperreality
  • · Replies 2 ·
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2

Distance, acceleration, and time

  • HopeDagger
  • · Replies 3 ·
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3