Asked by Jon
A current of 5.0 A flows for 20.0 minutes through a bulb and delivers 15000 J of electric energy to the bulb. What is the potential difference across the bulb?
A)2.5 V
B)4 V
C)100 V
D)100 V (book typo)
I was told to do this: energy= V*I*time in seconds solve for v. I don't really understand that so I did this: 5*1200= 3000 and 15000/3000= 2.5 so the answer is A
A)2.5 V
B)4 V
C)100 V
D)100 V (book typo)
I was told to do this: energy= V*I*time in seconds solve for v. I don't really understand that so I did this: 5*1200= 3000 and 15000/3000= 2.5 so the answer is A
Answers
Answered by
drwls
You did the math wrong twice, yet you ended up with the right answer, (A). You were just lucky.
15,000/3000 = 5 (not 2.5)
5A*1200s = 6000 Coulombs (not 3000)
Energy/Coulombs = voltage
Your method is an acceptable way to do the problem, and gives the right answer the numbers are done right.
Here is yet another way to do it
The power is P = 15000J/1200s = 12.5 W
12.5 = V*I
V = 12.5/5 = 2.5 V
15,000/3000 = 5 (not 2.5)
5A*1200s = 6000 Coulombs (not 3000)
Energy/Coulombs = voltage
Your method is an acceptable way to do the problem, and gives the right answer the numbers are done right.
Here is yet another way to do it
The power is P = 15000J/1200s = 12.5 W
12.5 = V*I
V = 12.5/5 = 2.5 V
Answered by
Jon
a small error in what I typed. I meant 5*1200= 6000 not 3000 duh and then 15000/6000 = 2.5 THATS what I did.
Answered by
exam in 3 weeks
DO YOU KNOW ANYTHING ABOUT RADIOACTIVE WASTE
There are no AI answers yet. The ability to request AI answers is coming soon!