Answer:
At point A, the cart has high potential energy. At point b, the cart is pulled down by gravity. At point c, the cart gains its highest kinetic energy. At point d, the cart returns back to the same state but with lower potential energy.
I'm actually going ahead in the book (DC Circuits) so this isn't really homework but I figured the tag was appropriate....the name of the chapter is Ohm's Law and Watt's Law.
<span>Problem: Calculate the power dissipated in the load resistor, R, for each of the circuits.Circuit (a): V = 10V; I = 100mA; R = ?; Since I know
V and
I use formula
P = IV: P = IV = (100mA)(10V) = 1 W.</span>
The next question is what I'm not sure about:
Question: What is the power in the circuit (a) above if the voltage is doubled? (Hint: Consider the effect on current).
What I did initially was: P = IV = (100mA)(2V) = 2 W
But then I looked at the answer and it said 4 W, then I looked at the Hint again. Then I remembered in the book early on it said "If the voltage increases across a resistor, current will increase."
So question is: When solving problems I have to increase (or decrease) current (I) every time voltage (V) is increased (decreased) in a problem, right? How about the other way around, when increasing current (I), you need to increase voltage (V). I'm pretty sure that's how they got 4 W, but want to make sure before I head to the next section of the book.
P = IV = (200mA)(2V) = 4 W
Answer:
1)ammeter
2)ised to check measure of current flow through a circuit
3)o.90 ambere
Answer:
Explanation:
Plate separation, d = 1.76 cm = 0.0176 m
Area of plates, A = 25 cm^2 = 0.0025 m^2
V = 255 V
(a) Capacitance of capacitor
C = 1.258 x 10^-12 F
charge is same before and after immersion as the battery is disconnected
q = C V
q = 1.258 x 10^-12 x 255 = 3.2 x 10^-10 C
(b)
Capacitance before, C = 1.258 x 10^-12 C
capacitance after, C' = k x C = 80 x 1.258 x 10^-12 = 100.64 x 10^-12 C
Where, k is the dielectric constant of water = 80
Potential difference after immersion, V' = V / k = 255 / 80 = 3.1875 V
(c) initial energy,
Final energy
