Physics help please?

This print-out should have 8 questions.

Multiple-choice questions may continue on

the next column or page { 藟nd all choices

before answering. The due time is Central

time.

Next Test Thursday March 27

001 (part 1 of 2) 10 points

The current in a certain resistor is 0.30 A

when it is connected to a potential di?erence

of 370 V.

a) What is the current in this same resistor

if the operating potential di?erence is 407 V?

Answer in units of A.

002 (part 2 of 2) 10 points

b) What is the current in the resistor when

the operating potential di?erence if 256 V?

Answer in units of A.

003 (part 1 of 2) 10 points

A 0:6 mile long copper wire that has a resis-

tance of 28 ohm is cut in half.

What is the resistance of one of the halves?

Answer in units of ohm.

004 (part 2 of 2) 10 points

What will be the new resistance if the two

halves are doubled over and used as one wire?

Answer in units of ohm.

005 (part 1 of 1) 10 points

An X-ray tube used for cancer therapy oper-

at

Physics help please?ballet

1.

0.30 * 407 / 370 = 0.33A.

2.

256 * 0.30 / 370 = 0.208A.

3.

28 * 0.5 = 14 ohm.

4.

14 / 2 = 7 ohm.