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.
Tension in a supporting thread after a second supporting thread is cut
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Entropy Change Confusion
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Hot air balloon question with bouyancy
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Pulley Problem on an Inclined Surface Using Energy Methods
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What is the tension in a charged ring?
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Pseudo Forces on a Mass in a Groove on a Rotating Disc
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Vertical Wall approaching Man - Impulse and Momentum Conservation
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How to calculate the moment of inertia of a rectangular cuboid?
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Potential energy of an electrostatic system in equilibrium
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Gauss' Law: Conductor, Insulator, Electric Field
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7
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Ambiguous question on momentum and how it works...
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13
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Find the work done by a spring using potential energy considerations
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4
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Relationship between pressure and temperature for liquids
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Archived Displacement and Momentum, particle in cathode ray tube with variables
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IBDP Extended Essay Ideas -- Help please
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Calculating Oscillation Period and Spring Energy in a Three-Mass System
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4
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Electric Field of a Toroid carrying a changing current I = kt on axis
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2
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Pulley system problem: 6 Pulleys and 1 Mass
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Signs in torque - different analyses using different sign notations?
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978
Why is the slope steeper in the given diagram?
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Are the 2nd and 3rd problems in this video correctly solved? (charged dipole and organ pipe problems)
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Mirror placed horizontally between two half convex lenses
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Billiard Ball, Conservation of Angular Momentum, Force below CM point
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6
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Two vertical bars are connected at the bottom via resistance......
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7
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What average power does the boy need to produce?
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12
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Projectile motion of two balls off a cliff
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Focussing a collimated beam using a diffraction grating
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Vertical spring & maximum length
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6
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Lens Maker's Formula - Confusion in the derivation
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15
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Energy of particle in simple harmonic motion
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13
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An ornament for a courtyard at a World's Fair is to be made up of four large metal spheres
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7
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Springs and Pulleys - Force analysis
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Confusion Calculating Young's Modulus
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5
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Looking at the color vs line spectrum
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How can I calculate the uncertainty of the mean with Gaussian error propagation?
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How to show 400 neutrinos are present?
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Change in apparent magnitude of a star after exploding
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3
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How do I correctly analyze the mass balance of a tractor seat?
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3
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Just looking for confirmation for a torque calculation
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I solved few questions on kinematics -- Is my working correct?
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Tension Question for Ship Container and Wind Gust
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Pressure and temperature phase diagrams
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Solving for Work Done When Accelerating a Mass
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Question about springs and rotational/translational energy
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Question about Rutherford experiment: Which of these could not be concluded?
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Equilibrium problem: Multiple forces acting on this hinged, supported beam
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Freefall chord through the Earth -- calculus proof
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Find the coefficient of stiffness of this spring (with non-negligible mass)
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Friction of a sliding mass on a slope
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Is it possible to measure SQRT(2) kg with a scale?
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Trying to understand the relationships between Forces, Mass and Inertia
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What would the voltmeters measure?
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Siren frequency heard by observer when an ambulance passes
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How to solve this kind of problem? (Mechanics Theory)
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Energy in simple harmonic motion--car problem
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Why am I calculating the unknown mass of ice incorrectly?
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Question about absorption line spectra
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What does it mean that when light is reflected the "wavelengths of each contributing hue are subtracted"?
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Newton's 3rd Law of Motion: Is the Punching Bag punching back?
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Oscillatory motion problem: Bicycle wheel rotation oscillation
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Pressure versus stress in uniformly charged sphere
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Doubts on Diodes -- Why is voltage shifted by 0.7V?
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Angular Momentum Conservation | Velocity at perigee
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Circuit with time varying current
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Determining the Change in Bulb Brightness by Changing Circuit
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What does the middle of a chain on a pulley mean?
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Constant acceleration problem: Dog chasing a surprised cat
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Two bars connected by a spring on a floor with friction
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The derivative of the dot product "distributes" over each vector
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Calculating the sum of displacement vectors
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A problem about the laws of conservation: Bullet colliding with a wood block
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Force on a point charge near a uniformly charged rod
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Two rods with fixed angle, find the velocity of the crossing point
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Stumped on mathematical proof
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A 50 cubic foot tank contains saturated 134a at 100F and a quality of 50%
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How can "work" done by a force be negative?
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Torque that a grounded infinite sheet exerts on a dipole
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Two tanks are connected by a valve and line
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Spring launcher firing steel balls
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Circular motion question: Mass on a rod rotating in a vertical circle
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Calculating Motor Force & Torque
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Bead on a rod which is being pulled by an ideal string with velocity v
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Appliance plug connected wrongly: live neutral earth
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Finding the direction of forces
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Finding parallel or in-series resistors
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Help needed on mass-energy equivalence
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Momentum: instantaneous or average?
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Derivation process of Selection Rule of hydrogenic atom
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A question about the perpendicular vector
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Trouble understanding frames in relativity
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Why does the PE of particles during steam condensation decrease?
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Torque on a sign hung by a hinge
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Acceleration of a ball at its max height after being thrown upwards
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Oscillation of fluids in a U tube
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A microwave oven of mass 13.0kg is pushed a distance 8.80m up a ramp
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Free-body diagram: Spring-loaded cylinder sliding on a metal rod
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A 2.8-kg block slides over the smooth icy hill -- Find the minimum speed to clear the pit
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A household fridge removes heat, determine power the fridge draws
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Find h in the problem involving a stone thrown upwards
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Voltage-resistance graph for this circuit with a variable resistance
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