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
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
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.
DO YOU KNOW ANYTHING ABOUT RADIOACTIVE WASTE
To find the potential difference across the bulb, you can use the formula:
Energy (E) = Potential difference (V) × Current (I) × Time (t)
Given:
Current (I) = 5.0 A
Time (t) = 20.0 minutes
However, before we proceed with the calculation, it's important to convert the time from minutes to seconds since the unit of time used in the formula is seconds.
1 minute = 60 seconds
So, 20.0 minutes = 20.0 × 60 = 1200 seconds
Next, let's rearrange the formula to solve for V:
V = E / (I * t)
Now, substitute the given values into the formula:
V = 15000 J / (5.0 A * 1200 s)
Simplifying the calculation:
V = 15000 J / 6000 A s
= 2.5 V
Therefore, the correct answer is A) 2.5 V.