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A 10.0 kg10.0\, \text{kg} box is pulled across a horizontal surface with a force of 50.0 N50.0\, \text{N} applied at an angle of 30∘30^\circ above the horizontal. The coefficient of kinetic friction is 0.250.25. (a) Draw a free-body diagram for the box.(b) Calculate the normal force acting on the box.(c) Find the net force acting on the box.(d) Determine the acceleration of the box.

A simple pendulum swings back and forth without air resistance. (a) Identify all forms of mechanical energy present in the system and describe how they change during the swing.(b) At what point is the speed of the pendulum the greatest? Justify your answer.(c) Explain why the total mechanical energy of the pendulum remains constant if no non-conservative forces act.

A parallel-plate capacitor is connected to a battery and becomes fully charged. The battery is then disconnected. (a) Explain what happens to the stored energy if the plates are moved farther apart.(b) What happens to the voltage across the plates?(c) Would your answers change if the battery remained connected? Explain why or why not.

A 0.75 m0.75\,\text{m} long wire carries 4.0 A4.0\,\text{A} perpendicular to a 0.60 T0.60\,\text{T} magnetic field.What is the magnetic force?

A square loop of wire is pulled at constant speed out of a uniform magnetic field that points into the page. (a) Describe the direction of the induced current in the loop.(b) What causes this current to be induced?(c) If the speed of the loop is increased, how does that affect the magnitude of the induced current?

A single rectangular wire loop of dimensions 0.20 m×0.30 m0.20\,\text{m} \times 0.30\,\text{m} is pulled out of a uniform 0.50 T0.50\,\text{T} magnetic field at a speed of 2.0 m/s2.0\,\text{m/s}. The magnetic field is perpendicular to the plane of the loop and into the page. (a) Calculate the change in magnetic flux as the loop completely leaves the field.(b) If the loop takes 0.10 s0.10\,\text{s} to exit the field, what is the average induced EMF?(c) If the loop has a total resistance of 2.0 Ω2.0\,\Omega, what is the average induced current?

Two parallel plates have an area of 0.020 m20.020\,\text{m}^2 and are separated by 0.0010 m0.0010\,\text{m}.What is their capacitance in picofarads?

If 0.60 C0.60\,\text{C} of charge flows through a wire in 12 s12\,\text{s},what is the average current?

A 10.0 μF10.0\,\mu\text{F} capacitor is connected in series with a 5.0 kΩ5.0\,\text{k}\Omega resistor and a 12.0 V12.0\,\text{V} battery. (a) Calculate the time constant τ\tau for the circuit.(b) What is the voltage across the capacitor after 2.0 s2.0\,\text{s} of charging?(c) How much charge is on the capacitor at that time?

Calculate the resonance frequency of a free electron in a magnetic field poised at 0.53 T using a ge value of 2.0023