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Household wiring often uses 2.0 mm diameter copper wires. The wires can get rather long as they snake through the walls from the fuse box to the farthest corners of your house. What is the potential difference across a 18 m long, 2.0 mm diameter copper wire carrying an 7.0 A current?  (Resistivity of copper = 1.7 x 10-8 

a) How long must a 0.52 mm diameter aluminum wire be to have a 0.44 A current when connected to the terminals of a 1.5 V flashlight battery? (Resistivity of aluminum = 2.8 x 10-8

A 4.00 

In the figure shown below, q = -1.0 nC. What is the electric potential at the point indicated with the black dot? Make sure to include units. 

A water molecule perpendicular to an electric field has 1.30×10−21 J more potential energy than a water molecule aligned with the field. The dipole moment of a water molecule is 6.2 x 10-30 Cm. What is the strength of the electric field?

A capacitor is formed from two 2.0 cm x 2.0 cm electrodes spaced 1.0 mm apart. The electrodes are charged to 

a) How long must a 0.62 mm diameter aluminum wire be to have a 0.48 A current when connected to the terminals of a 1.5 V flashlight battery? (Resistivity of aluminum = 2.8 x 10-8

The electric field strength is 4.80×104  N/C inside a parallel-plate capacitor with a 1.90 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)

How much charge does a 9.0 V battery transfer from the negative to the positive terminal while doing 21 J of work?

Maria owns a small convenience store, and unfortunately very small, shoplifting related losses occur at her store quite frequently (at least once per week). For the past year she has hired a security guard to attempt to minimize the likelihood of shoplifting occurring. However, after her own analysis she believes she is paying too much for the security guard’s services. Instead of paying for risk prevention technique, Maria has made the decision to set aside money each month to pay for these very low severity and rather predictable shoplifting losses. Which method of risk financing is Maria practicing?