{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

15_Ch 17 College Physics ProblemCH17 Current and Resistance

# 15_Ch 17 College Physics ProblemCH17 Current and Resistance...

This preview shows page 1. Sign up to view the full content.

Current and Resistance 83 (b) The energy used by the oven in 5.0 h is () 3 1 kW 20.0 C s 220 J C 5.0 h 22 kWh 10 J s Et I Vt   =⋅∆= ⋅∆= =     P and the cost of this energy, at a rate of \$0.12 per kilowatt-hour is ( ) 22 kWh \$0.12 kWh \$2.6 cost E rate =⋅ = = 17.33 The maximum power that can be dissipated in the circuit is ( ) ( )( ) 3 max max 120 V 15 A 1.8 10 W VI =∆ = = × P Thus, one can operate at most 18 bulbs rated at 100 W per bulb. 17.34 (a) The power loss in the line is ( ) ( ) 2 2 7 1000 A 0.31 km 160 km 5.0 50 MW loss IR == = P (b) The total power transmitted is ( )( ) 38 700 10 V 7.0 700 MW input = × = × = P Thus, the fraction of the total transmitted power represented by the line losses is
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Ask a homework question - tutors are online