A long wire is carrying a current of 3 A a.  Calculate the magnitude of the magnetic field at point is a distance of 15 cm from the wire.

A 2.0-μF capacitor is charged to 12 V and then discharged through a 4.0 × 106 Ω resistor.  How long will it take for the charge on the capacitor to drop by 60% of its initial value ?

The power being delivered to a resistor is 0.800 W. The value of the resistor is 400 Ω. What is the voltage across the resistor?   

The power being delivered to a resistor is 0.800 W. The value of the resistor is 400 Ω. How much energy is delivered to the resistor in 2 minutes? 

In the below fig. the values of the resistances are 50 Ω for resistor A, 100Ω for resistor B, and 300 Ω for resistor C. The battery has a voltage V = 15 V. Find the current in resistor C.

A 2 m long wire is perpendicular to a magnetic field of 0.3 T.  If the wire experiences a force of 0.56 N, calculate the current in the wire.

Two capacitors of capacitance 9 uF and 12 uF are connected in series and a 20 V battery.  Find the equivalent capacitance. 

Two point charges are located on the x-axis.  Charge q1 = 3 uC (u = 10^-6) is located at the origin and the second charge is at x = 0.4 m.  Find the value and sign of the second charge if it is experiencing an electric force of 0.23 N directed to the right.

Two point charges are located on the x-axis. Charge q1 = 6 uC is located at the origin and charge q2 = -3 uC is located at x = 2 m.  Find the work required to bring in a 2 uC charge from far away and place it at y = 1 m on the y-axis (point (0,1)). 

Two charged parallel plates are separated by 2 cm. The plates are charged and create a uniform electric field of 600 N/C between the plates.  If a 3 uC charge of mass 3 g is placed at the positive plate and released from rest, what will be its speed when it reaches the negative plate? (This is the same setup as last question)