PhysicsClassical Physics
Work Energy Theorem: Stopping a 950 kg Car over 120 m and 2.00 m
Use the work energy theorem to compare the average net forces that stop a 950 kg car from 90.0 km/h over 120 m and over 2.00 m.
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PhysicsClassical Physics
Capacitance: Charge and Energy of 2.00 μF and 7.40 μF Capacitors at 9.00 V
Calculate charge and stored energy for two capacitors across a 9.00 V battery, with separate results for series and parallel connections.
PhysicsClassical Physics
Coulomb's Law: Separation of Two 75.0 nC Charges Exerting 1.00 N
Rearrange Coulomb's law to find the distance between equal 75.0 nC point charges when their force has magnitude 1.00 N.
PhysicsClassical Physics
Kirchhoff's Circuit Laws: Three Branch Currents with 18 V and 45 V Sources
Use one junction equation and two loop equations to find three branch currents, including a current that runs opposite to its reference arrow.
PhysicsMaterials Science
Photoelectric Effect: Maximum Electron Energy for Sodium under 450 nm Light
Calculate the photon energy of 450 nm light and subtract sodium's stated 2.28 eV work function to find the maximum photoelectron kinetic energy.
PhysicsThermodynamics
Carnot Cycle: Maximum Work Between 200 °C and 20 °C
Use kelvin temperatures to find the Carnot efficiency limit, maximum work output, and rejected heat for a two-reservoir engine.
PhysicsThermodynamics
Maxwell-Boltzmann Speed Distribution: Oxygen Between 100 and 150 m/s
Integrate the Maxwell-Boltzmann speed density for oxygen at 250 K over 100–150 m/s and report the molecular fraction to two significant figures.
PhysicsClassical Physics
Time Dilation: Earth-Frame Lifetime of a Muon Moving at 0.950c
Identify the muon proper time and use the Lorentz factor to calculate the lifetime measured by an Earth observer.
PhysicsClassical Physics
Diffusion Compton (Compton Scattering): A 71 pm X-Ray at 30°
Solve the 30° Compton-scattering wavelength shift for a 71 pm X-ray and identify the maximum shift at backscattering.