A solar cell generates a potential difference of 0.320 V when a 445.0 ? resistor is connected across it and a potential difference of 0.504 V when a 945.0 ? resistor is substituted.

A) What is the internal resistance of the cell in Ohms?

B) What is the emf of the cell?

C) The area of the cell is 27.0 cm² and the rate per unit area at which it receives light energy is 58.0 mW/ cm². What is the efficiency of the cell for converting light energy to thermal energy in the 945.0 ? external resistor?

A ceiling fan consists of a small cylindrical disk with 5 thin rods coming from the center. The disk has mass md = 3.1 kg and radius R = 0.24 m. The rods each have mass mr = 1.3 kg and length L = 0.75 m.

1) SOLVED ALREADY BACKGROUND INFO

moment of inertia of each rod about the axis of rotation = .24kg-m²

^{2) SOLVED ALREADY BACKGROUND INFO} moment of inertia of the disk about the axis of rotation = .09kg-m²

What is the moment of inertia of each rod about the axis of rotation

3) What is the moment of inertia of the whole ceiling fan?

4) When the fan is turned on, it takes t = 3.1 s and a total of 12 revolutions to accelerate up to its full speed. What is the magnitude of the angular acceleration?

5) What is the final angular speed of the fan?

When the electricity goes out on your campus, a backup source powers the servers that handle communications and the internet. Rather than use batteries, many installations use a flywheel, a heavy rotating disk that spins, very rapidly with nearly zero friction. An electric motor spins up the flywheel, which continues to spin with very little energy input. When the ststem needs to provide power, the flywheel's motion is used to turn an electric generator. A typical system has a 540 kg cylinder with a radius of 0.30 m. A small electric motor provides a constant 2.8 N-m torque to spin up the cylinder. A) Calculate the frequency for cylinder s motion? B) Calculate angular speed in rad/s? C)Calculate moment of inertia of the cylinder? D) Calculate the angular acceleration?

1. Consider the following nuclides:

                                          NUCLIDE                             MASS (amu)

                                                  ₅¹¹B 11.009305

                                                ₆¹²C 12.0000

₄₂¹⁰⁰Mo 99.90747

                                                ₈₃²⁰⁹ Bi 208.97973

                                                ₉₂²³⁸ U 238.050

For each of these nuclides, find (a) the binding mass in atomic mass units and (b) the binding energy in Mev.

2. (a) Find the average binding energy per nucleon of each nuclide listed in problem 1, and (b) mark the location of each nuclide on the attached graph of average binding energy per nucleon versus atomic mass number.

3. Find the average radius of each nuclide, listed in problem 1.

A pendulum of length l with a ball of mass m is raised 90◦ clockwise from its hanging position and released. A block of mass 2m rests on a frictionless surface at the pendulum’s hanging position so that it is struck just as the pendulum reaches its lowest point. The two objects collide elastically and the pendulum rebounds, swinging back up to an angle θ clockwise from the vertical. What is the angle θ, and what is the speed of the block after the collision?

An empty parallel plate capacitor is connected between the terminals of a 10.7-V battery and charged up. The capacitor is then disconnected from the battery, and the spacing between the capacitor plates is doubled. As a result of this change, what is the new voltage between the plates of the capacitor?

Please Show Work

An express subway train passes through an underground station. It enters with an initial velocity of 22.0 m/s and decelerates at a rate of 0.150 m/s^2 as it goes through. The station in 210 m long.
a. How long is the nose of the train in the station?





b. How fast is it going when the nose leaves the station?





c. If the train is 130 m long, when does the end of the train leave the station?





d. What is the velocity of the end of the train as it leaves?

Discuss Lenz's Law in terms of Faraday's Law and induced current (Requires website source)

A 4.5 mL syringe has an inner diameter of 6.0 mm , a needle inner diameter of 0.29 mm , and a plunger pad diameter (where you place your finger) of 1.2 cm. A nurse uses the syringe to inject medicine into a patient whose blood pressure is 140/100. Assume the liquid is an ideal fluid.

A. What is the minimum force the nurse needs to apply to the syringe?

B. The nurse empties the syringe in 5.0 s . What is the flow speed of the medicine through the needle?

A rocket carrying a new 990-kg satellite into orbit misfires and places the satellite in an orbit with an altitude of 120 km, well below its operational altitude in low-Earth orbit.

(a) What would be the height of the satellite's orbit if its total energy were 545 MJ greater?
km

(b) What would be the difference in the system's kinetic energy? (Include the sign of the value in your answer.)
MJ

(c) What would be the difference in the system's potential energy? (Include the sign of the value in your answer.)
MJ

The driver of a 1450 kg car, initially traveling at 10.6 m/s, applies the brakes, bringing the car to rest in a distance of 24.0 m. Find the net work done on the car. Find the magnitude and direction of the force that does this work. (Assume this force is constant.)

A cyclist coasts up a 10.3° slope, traveling 19.0 m along the road to the top of the hill. If the cyclist's initial speed is 9.90 m/s, what is the final speed? Ignore friction and air resistance.

Find the minimum initial height h₁ of the roller coaster in the figure below if the roller coaster is to complete the loop, where h₂ = 24.6 m. Neglect friction.

the specific heat of copper (0.092) and the specific heat of silver is (0.056). The mass of silver is 1.02 times greater than the mass of the copper. The heat gained by the silver is 1.33 times the heat gained by copper. The temperature change of copper is 20 degrees Celsius. What is the temperature change of the silver?

An explosion aboard a stationary spacecraft breaks it into 3 well-defined and identifiable pieces. From a space station you capture a video of the explosion. A 2500-kg piece flies off at 200 m/s in the –x-direction (as seen on the video monitor), a 1500-kg piece moves away at 220 m/s at an angle of 34° above the +x axis. The third piece you know to be 1800 kg but its path cannot be seen on the video. You want to know which way it’s headed in case it moves toward another space station. What is the velocity of this third fragment? Assume all the pieces lie in the same (xy) plane.