# Physics

(a) How much charge does a battery have to supply to a 5.0 uF capacitor to create a potential difference of 1.5 V across its plates? How much energy is stored in the capacitor in this case? (b) How much charge would the batter have to supply to store 1.0 J of energy in the capacitor? What would be the potential across the capacitor in this case.

Once again, I am lost!!!

1. 👍 0
2. 👎 0
3. 👁 199
1. a) C = q/V so q = C V
= 5*10^-6 * 1.5
= 7.5 * 10^-6 Coulombs

now do E = (1/2) C (1.5)^2 to get energy
E = .5 (5*10^-6)(2.25)
E = 5.63*10^-6 Joules

b) Luckily we derived this in your last question, but now that I see your questions you probably have it in your book and have not had calculus so
E = (1/2) C V^2 from your book or the other problem
E = (1/2) C (q/C)^2
(q/C)^2 = 2 E/C
q^2/C^2 = 2 E/C
q^2 = 2 E C
q = sqrt (2E*C)
q = sqrt (2 * 5 * 10*-6)
q = 10^-3 sqrt (10)
q = 3.16 * 10^-3 coulombs

c)V = q/C = 2.24*10^-3 / 5*10^-6
V = .447* 10^3 = 447 volts, watch out

1. 👍 0
2. 👎 0
posted by Damon

## Similar Questions

1. ### Science

1. What is the direction of charge flow when charging a capacitor? When discharging a capacitor? What is your evidence? 2. Consider a circuit with a capacitor, battery, wire, and bulb. Describe the source(s) of charge during

asked by Ronnie on October 1, 2010
2. ### physics

Having trouble with this one: A capacitor having a capacitance of 10uF is charged by 100v battery. A.)Calculate the charge on the capacitor? B.)calculate the energy stored in the capacitor? C.) the terminals of the capacitor is

asked by morgan on February 28, 2010
3. ### physics

parallel plate capacitor has an area of 5cm^2 and a capacitance of 3.5PF. the capacitor is connected to a 12v battery .after the capacitor is completely charge up the battery is removed. a)what must be the separation of the plates

asked by selina on February 15, 2016

parallel plate capacitor has an area of 5cm^2 and a capacitance of 3.5PF. the capacitor is connected to a 12v battery .after the capacitor is completely charge up the battery is removed. a)what must be the separation of the plates

asked by selina on February 15, 2016
5. ### AP PHYSICS

A 3.0-uF capacitor and a 4.0-uF capacitor are connected in series across a 40.0-V battery. A 10.0-uF capacitor is also connected directly across the battery terminals. Find the total charge that the battery delivers to the

asked by Becky on April 1, 2008
6. ### Physic II

Suppose a capacitor of C=2.0 uF with no excess charge on it is suddenly connected in series with a resistor of R=447 ohms , and an ideal battery of voltage V=25 V . How long will the capacitor take to gain 80% of the charge it

asked by Yolune on March 13, 2014
7. ### physics

Three capacitors are connected to a battery of unknown voltage as shown in the circuit diagram above. The voltage drop across capacitor C 1 is V 1 = 11 . volts. a) What is the effective capacitance of the three capacitors? c) What

asked by selina on February 17, 2016
8. ### physics

A 9 V battery is connected in series with a 100 Ω resistor and 12µF capacitor. The capacitor is initially uncharged. What is the capacitive time constant of the circuit? How much charge q(t) is in the capacitor after two time

asked by Anonymous on March 8, 2012
9. ### Physics

Could someone please tell me what equations i am suppose to use to work out these problems. A capacitor in RC circuit has two overlapping plates of width 3.40 m and length 8.90 m separated by 2.60 cm. A dielectric of dielectric

asked by Sam on May 4, 2010
10. ### physics

9-Volt battery is used to charge a 375 mF capacitor over a 147 Ù resistance. How many seconds will it take for the capacitor to reach 75% of its maximum charge? Hint: The equation below represents the charge of a charging

asked by crystal on March 10, 2011

More Similar Questions