Homework Clinic
Science Clinic => Physics => Topic started by: codyclark on Jul 29, 2018
-
The lamps in a string of decorative lights are connected in parallel across a constant-voltage power source. What happens if one lamp burns out? (Assume negligible resistance in the wires leading to the lamps.)
A) The brightness of the lamps will not change appreciably.
B) The other lamps get brighter equally.
C) The other lamps get brighter, but some get brighter than others.
D) The other lamps get dimmer equally.
E) The other lamps get dimmer, but some get dimmer than others.
Question 2
The melting point of aluminum is 660C, its latent heat of fusion is 4.00 105 J/kg, and its specific heat is 900 J/kg K.
If 300 kJ of thermal energy are added to 442 g of aluminum at 100C, what is the final state of the system? That is, how much is liquid, how much is solid, and what is its temperature?
-
Answer to Question 1
A
Answer to Question 2
The system will be at 660C, with 249 g of solid and 193 g of liquid aluminum.