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.
Why Was My Answer of 63 cm for the Focal Length of a Converging Lens Incorrect?
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Drone dragging a hose behind it
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Torque biomechanics
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(Answer check) for a work problem
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784
Question related two different ways to do solution
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CO2-powered metric racer car competition | help please?
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Force acting on one side of a fluid
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1K
Coefficient of Restitution for a Hypothetical Collision where masses are not equal after the collision compared to before the collision
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Confusion regarding surface tension direction and force balance
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Convert to Center of Mass Reference Frame
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How far from the point of release will the ball hit the ground?
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996
Irodov 1.23 confusion: Calculate distance traveled and time elapsed for this decelerating particle
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990
What is force? How can we interpret the full definition of force?
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892
Calculate velocities in COM reference frame for 2D collision
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Inclined plane problem
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AP physics 2: Phase change in thin film interference
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892
Calculate the speed and angle of the center of mass before a collision
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1K
Mastering physics homework: Mass oscillating on a vertical spring
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780
Friction direction change in a inclined circular bend (car on a road)
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1K
Induced current and force on circular loop in varying magnetic field
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Problem on Radiation Pressure
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Quick Physics Questions I found online and need explanations solving
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881
Calculate the energy transferred given the voltage, current and time
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815
This 3 mass atwood problem is confusing me
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4
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1K
Left-to-Right Wave — How Does Particle X Move?
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Computing the moment of inertia for a rotary inverted pendulum
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Ball on a string thrown around a spool
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1K
Network Analysis, Kirchhoff's Laws, changing current source to voltage
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Graphs of RC Circuit Responses
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The problem of one tube and two balls on a plane
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Calculating the Forces on a Charge
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Ambiguous Problem Statement on Determining Speed of Aircraft
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How does a transistor act as an amplifier?
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972
How do I find the intersection of the wrench's LOA?
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1K
Momentum: why don't the two carts become one?
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How to calculate the errors in the measured period of a pendulum?
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835
Series and Parallel Circuits using symmetry
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10
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969
How is the slider connected to the switch?
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6
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914
Thermal expansion of a glass rod and a metal ruler
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8
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929
A problem from a physics national competition
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1K
Change in entropy of the surroundings in an irreversible process
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14
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1K
Surface current of superconducting sphere in magnetic field
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Force of car pushing on a truck
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1K
Force needed to raise a backpack
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843
Uniform circular motion angle relationship
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725
Simulating a Rotary Inverted Pendulum in Python
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Pressure of water coming out of a hose nozzle
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Focal length of the eyepiece lens in a compound microscope
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Find the magnitude of the child's acceleration
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Why are these forces not included in the solution? (Torque Problem)
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Why do compasses always point in the wrong direction?
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Charge on disk with non uniform surface charge density
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Optics problem with a glass lens immersed in water
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Homework: Can a rest frame be chosen for the center of momentum for a system of two photons?
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1-dimensional kinematics - final velocity of 2 trains in opposing direction
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Total energy of a wave on a string
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What happens to the position of two attracting charges when a conductor is inserted between them?
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Spring force required to overcome friction between two blocks
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Rolling without slipping problem
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Stopping a rod moving with constant omega
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Handling two SHMs in different directions
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Sound in an Open Vertical Tube partially filled with Water
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Best Egg Drop Contest Shock Absorber?
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Problem involving SHM and a collision
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Calculate the velocity of the canoe relative to the water
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Amplitude of a stretched spring that is stretched further
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Waves on a String Fixed at the Ends
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Electric Potential Energy of Point Charge Systems
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Landing reusable booster rockets
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Problem with the power of car
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Tangential velocity of external satellite
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Will my weather balloon work in the Stratosphere?
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Angular momentum- rotating rod
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Transverse mechanical waves in a steel wire
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Thermodynamics - Dryness fraction Equations
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Dryness fraction of saturated steam
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help whit problem of college admission exam
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Loop equations for this battery-resistor circuit
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Work done to insert a point charge 𝑞 at the center of a conducting sphere
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Understanding a math step in solving Schrödinger's equation for single particle in a box
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Center of mass and momentum- A question about systems
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Circle approximation of a wave pulse on a string or spring
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Calculating magnetic field outside a solenoid
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Aerodynamics: Optimization of an aircraft engine
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639
I do not understand why the extra 2 factor is there (energy of 1D electron gas at zero temperature)
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Rotating ring on a rough surface- but with a twist
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Electric potential of nested spherical shells
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Another rotation problem -- Acceleration of a ring rolling on a surface
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Why is it necessary to start this experiment with the water level at 400mL?
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Correct statement about light transmitted and reflected by windscreen
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Force pulling on a string at an angle with a block at the other end
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Confusion about friction in rotating ring
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Problem n. 7 chapter 4 Eisberg Resnick "Quantum Physics"
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A block dropping onto a spring system
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Paper 'helicopter' experiment - Adding Weight Decreases Flight Time?
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When are reactive forces enough to support this body?
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Can A Vector Have Components Of Say Y or Z in the X-Hat Direction?
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A problem about momentum and the elastic collision of two particles
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Identical Batteries in Parallel do not Draw Same Current, Non-Ideal?
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Homework assignment that I was able to solve using EDO, but need to use Laplace now
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