Exercise 1

Hoe much would you have to raise the temperature of a copper wire (originally at 20 degrees Celsius) to increase it's resistance by 18%? Assume the temperature coefficient of resistivity of copper is 0.0039 (degrees Celsius )^-1. Answer using two significant figures.

Exercise 2

A service station charges a battery using a current of 6.2A for 6.0 h. How much charge passes through the battery? Answer using two significant figures. Delta Q= ? C

Exercise 3

Suppose a current is given by the equation I=1.60sin(170t), where I is is amperes and t is in seconds.

1-What is frequency? (answer in three significant figures)

2-What is the rms value of the current? ( answer in three significant figures)

3-

Part A Calculate the peak current in a 2.5 -k$2 resistor connected to a 220-V rms ac source. Express your answer using two significant figures.Suppose that this is the current through a 28.0 02 resistor. Select the correct equation that describes the voltage as a function of time O -0.0571 sin(170#) V O - 28.0 sin(170t) V 44.8 sin(170t) V -44.8 sin(1706) V 0.0571 sin(1706) V 28.0 sin(170t) VPart A Compute the voltage drop along a 30-m length of household no. 14 copper wire (used in 15-A circuits). The wire has diameter 1.628 mm and carries a 10-A current. The resistivity of copper is 1.68x10 8 12 . m Express your answer to two significant figures and include the appropriate units