Explanation:
a. KE at bottom = PE at top
½ mv² = mgh
v = √(2gh)
v = √(2 × 9.8 m/s² × 20.0 m)
v = 19.8 m/s
b. Work by friction = PE at top
mgμ d = mgh
d = h / μ
d = 20.0 m / 0.210
d = 95.2 m
That's a <em>parallel</em> circuit. <em>(B)</em>
When current from Point-A reaches the 3-way intersection just to the right of Point-B, it has to make a choice: Either turn left, go through B, and light the lower bulb, or go straight and light the upper bulb.
A circuit that has any "decision" points in it is a parallel circuit. What happens in the real world is: The current splits up. Some of the current that reaches the intersection turns left toward Point-B, and the rest of it goes straight up.
A series circuit is one in which there's only one possible path all the way around. There are no intersections of more than 2 roads, and no electron ever has to decide which way to flow.
An open circuit is one in which there's a break somewhere along the line and electrons can't jump across it. It's like a railroad where a big piece is cut out of the track somewhere. So no trains can travel on that route, and there's no current flowing anywhere in the circuit.
I'm not so sure about a "combination" circuit. I guess you could give that name to a complicated circuit that has some series parts and some parallel-parts. Personally, I'd call that a "series-parallel" circuit. But it really doesn't matter right now. Whatever the word means, the circuit in the picture is definitely not a "combination" circuit.
-- Radio waves. (To hear the weather while I'm waking up.)
-- Light waves. (To see where the dog is so I don't step on him.)
-- Infrared waves. (To make my toast for breakfast.)
-- Microwaves. (To heat my oatmeal for breakfast. Also when I go in to my job as a microwave communications engineer.)
<span>The answer is C. A scale would include a series of eight notes, where the first and seventh notes have the same letter.
Just took the test. Got 100%
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