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How much charge does a 9.0 V battery transfer from the negative to the positive terminal while doing 28 J of work?

The voltage across the terminals of a 9.0 V battery is 8.3 V when the battery is connected to a 45

In proton-beam therapy, a high-energy beam of protons is fired at a tumor.  As  the protons stop in the tumor, their kinetic energy breaks apart the tumor’s DNA, thus killing the tumor cells. For one patient, it is desired to deposit 0.09 J of proton energy in the tumor. To create the proton beam, protons are accelerated from rest through a 9.0×103 kV potential difference. What is the total charge of the protons that must be fired at the tumor? 

Two 4.8 cm x 4.8 cm metal plates are separated by a 0.21 mm thick piece of Teflon. (Dielectric constant for Teflon (

Motional emf: A conducting bar slides without friction on two parallel horizontal rails that are 50 cm apart and connected by a wire at one end. The resistance of the bar and the rails is constant and equal to 0.10 Ω. A uniform magnetic field is perpendicular to the plane of the rails. A 0.080-N force parallel to the rails is required to keep the bar moving at a constant speed of 0.50 m/s. What is the magnitude of the magnetic field?

The electric field strength is 5.50×104  N/C inside a parallel-plate capacitor with a 2.50 mm  spacing. A proton is released from rest at the positive plate. What is the proton’s speed when it reaches the negative plate? (mass of proton = 1.67 x 10-27 kg, charge of an proton = 1.60 x 10-19 C)

The electric field strength is 4.90×104  N/C inside a parallel-plate capacitor with a 2.50 mm  spacing. A proton is released from rest at the positive plate. What is the proton’s speed when it reaches the negative plate? (mass of proton = 1.67 x 10-27 kg, charge of an proton = 1.60 x 10-19 C)

The electric field strength is 4.60×104  N/C inside a parallel-plate capacitor with a 2.20 mm  spacing. A proton is released from rest at the positive plate. What is the proton’s speed when it reaches the negative plate? (mass of proton = 1.67 x 10-27 kg, charge of an proton = 1.60 x 10-19 C)

LR circuits: A 45-mH ideal inductor is connected in series with a 60-Ω resistor through an ideal 15-V DC power supply and an open switch. If the switch is closed at time t = 0 s, what is the current 7.0 ms later?

a) How long must a 0.60 mm diameter aluminum wire be to have a 0.54 A current when connected to the terminals of a 1.5 V flashlight battery? (Resistivity of aluminum = 2.8 x 10-8