<p>
[quote]
actually, the other option of 1000 * 70% = 630 joules of waste
[/quote]
</p>
<p>???(10char)</p>
<p>there was an option of 1000 w and 30% efficiency. That actually has the most energy wasted.</p>
<p>Damn... Got that wrong :(</p>
<p>Yes, 1000W & 30% efficiency was the one with most energy wasted because:</p>
<p>efficiency = input/output</p>
<p>Output = input/efficiency</p>
<p>Therefore we want the largest possible number from that ratio..1000W & 30% efficiency gives you that. One other option was 1000W & 40% efficiency but that gives you a lower number.</p>
<p>Btw, lobstar, if you remember 70+ questions could you please post them all? It would be greatly appreciated and extremely useful for all of us..</p>
<p>Thanks.</p>
<p>alright...i'll make a list...expect it tomorrow (actually it's 12:30 am, so later today, ha)</p>
<p>since i like to be organized, and don't feel like doing hw right now...here a third of the questions...</p>
<p>1) Which one is NOT a fractal?
2) A sheet of metal has a hole in it. When the temperature decreases, the sheet contracts. what happens to the hole?
3) Two balls are of uniform density. The more massive one falls faster. Why?
4) Iron at 100 deg C is mixed with water at 20 deg C. The resulting temperature of the mixture is closer to 20 than 100. Why?
5) Light goes through two polaroids. First one has a vertical axis, second horizontal. What is the direction of the light that passes through the second one?
6) Resistance in wire is affected by:
I. length
II. cross-sectional area
III. temperature
7) What is the magnitude of the electric field in the capacitor below?
8) In which diagram is there no net force on the proton?
9) In which diagram is the net force on the proton in the plane of the page and upwards?
10) A light bulb is in a container with no air. Heat is transferred through:
I. conduction
II. convection
III. radiation
11) ___________ _____________
|____<strong><em>| --------d-------->|</em></strong>_______|
which of the following describe the amount of work done?
I. mgd
II. Fd
III. 1/2mv^2
12) The distance from the earth to the moon is 60x the distance the radius of the earth. what is the ratio of the grav. field strength at the moon vs. at the surface of the earth?
13) when an object falls it loses what kind of energy?
14) when an electron hits a television screen it loses what kind of energy?
15) you are underwater and look at a bird above water. where do you see the bird (relative to where the bird actually is)?
16) (Graph showing this) force of 200 N exerted for 0.1 s. What is the object's change in momentum?
17) Four spaceships traveling at 0.1c, 0.2c, 0.5c, and 0.8c pass by an asteroid. Which one measures the longest length for the asteroid?
18) What did Galileo NOT discover?
19) Piston problem (pushing/pulling/nothing, adding/taking away heat, or nothing)
20) period of a pendulum is T. what is the new period when its amplitude is doubled?
21) picture of a wave. at which of the points is the wave moving up?
22) you have a coil of copper and a magnet. what do you need to do to induce a current in the coil?
23) when is the potential energy of jupiter the greatest?
24) one plane moves due west; second one due north. what is the direction of the second plane relative to the first one?
25) positive charge is shot across a capacitor (top is negative, bottom is positive). what is the path of the charge?</p>
<p>too tired...someone else can do the answers and the rest of the questions</p>
<p>Awesome.</p>
<p>1) Which one is NOT a fractal?
Insect</p>
<p>2) A sheet of metal has a hole in it. When the temperature decreases, the sheet contracts. what happens to the hole?
Hole contracts as well.</p>
<p>3) Two balls are of uniform density. The more massive one falls faster. Why?
Greater mass-to-area ratio</p>
<p>4) Iron at 100 deg C is mixed with water at 20 deg C. The resulting temperature of the mixture is closer to 20 than 100. Why?
*Answer has to do with specific heat capacities</p>
<p>5) Light goes through two polaroids. First one has a vertical axis, second horizontal. What is the direction of the light that passes through the second one?
No light passes through.</p>
<p>6) Resistance in wire is affected by:
all of them..
<strong>But I don't remember the question being phrased this way and I know the answer I put was only temperature. Could someone clarify this question?</strong></p>
<p>7) What is the magnitude of the electric field in the capacitor below?
?? Don't remember this question..could someone please answer this/clarify the question?</p>
<p>8) In which diagram is there no net force on the proton?
Don't remember this question.</p>
<p>9) In which diagram is the net force on the proton in the plane of the page and upwards?
Don't remember this question either.</p>
<p>10) A light bulb is in a container with no air. Heat is transferred through:
III. radiation</p>
<p>11) ___________ _____________
|____<strong><em>| --------d-------->|</em></strong>_______|
which of the following describe the amount of work done?
II. Fd & III. 1/2mv^2</p>
<p>12) The distance from the earth to the moon is 60x the distance the radius of the earth. what is the ratio of the grav. field strength at the moon vs. at the surface of the earth?
3600/1</p>
<p>13) when an object falls it loses what kind of energy?
Gravitational Potential Energy</p>
<p>14) when an electron hits a television screen it loses what kind of energy?
Kinetic Energy</p>
<p>15) you are underwater and look at a bird above water. where do you see the bird (relative to where the bird actually is)?
Above the surface of the water, above its original position.</p>
<p>16) (Graph showing this) force of 200 N exerted for 0.1 s. What is the object's change in momentum?
Change in momentum = Ft = 200 * 0.1 = 20kgms</p>
<p>17) Four spaceships traveling at 0.1c, 0.2c, 0.5c, and 0.8c pass by an asteroid. Which one measures the longest length for the asteroid?
The asteroid has the longest length when a person ON the asteroid measures it, not on the spaceships. Answer : the asteroid</p>
<p>18) What did Galileo NOT discover?
Galaxies moving apart - This is red shift which is modern.</p>
<p>19) Piston problem (pushing/pulling/nothing, adding/taking away heat, or nothing)
Don't remember this problem.</p>
<p>20) period of a pendulum is T. what is the new period when its amplitude is doubled?
Amplitude does not affect period because:</p>
<p>T = 2pi * root L/g
<strong>Btw, wasn't this question SPRING not Pendulum? Or I could've remembered incorrectly...either way someone double check my answer. I'm not sure</strong></p>
<p>21) picture of a wave. at which of the points is the wave moving up?
D</p>
<p>22) you have a coil of copper and a magnet. what do you need to do to induce a current in the coil?
Move them relative to each other.</p>
<p>23) when is the potential energy of jupiter the greatest?
When it is furthest away.
<strong>I don't remember this being one of the questions..was it?</strong></p>
<p>24) one plane moves due west; second one due north. what is the direction of the second plane relative to the first one?
Northwest</p>
<p>25) positive charge is shot across a capacitor (top is negative, bottom is positive). what is the path of the charge?
Parabolic</p>
<p>These were the questions I didn't answer/answer completely:4,7,8,9,11,19,20
(Answered more of them thanks to anonamous)</p>
<p>because I couldn't remember them and the way it was phrased here didn't really tell me much. Could someone either answer them or rephrase them so that I can remember/understand them better? </p>
<p>Thebillsfan could you post as many more questions as possible (another third or the rest would be great)? Thanks. :)</p>
<p>4) to do with specific heat capacity
6) resistance is affected by all of them
21) i believe it was B (i may remember wrong)</p>
<p>That resistance in the wire thing I believe the question is wrong. I remember it was asking something else and that the answer was only temperature. Do you remember what the question was exactly?</p>
<p>3) mass-to-area ratio
11) II and III</p>
<p>EDIT: this is the question as i remembered
Resistance in wire is affected by:
I. length
II. cross-sectional area
III. temperature</p>
<p>anonamous could you tell me what question 11 was? as in the question? I couldn't remember it at all.</p>
<p>Yes sure... q. 11 shows a block that moves is moved from one position to a new position by force F applied to it. The movement is only horizontal making its gravitational potential energy doesnt change. the FxD is obvious, but also kinetic energy can also be used since it gains velocity** and the work done is transferred to the form of kinetic only (assuming no friction or energy loss)</p>
<p>therefore, answer: II & III</p>
<p>**EDIT</p>
<p>Hm..okay thanks. XD I remember it now, but I can't remember what answer i put.</p>
<p>Meh. Wish I had a good memory, then I could post more questions. XD</p>
<p>Dont worry... if you can do q.11 right now it is likely that you also did it correctly in the test... i can barely remember the questions myself, at least until aznoverachiever reminded me of some of them...</p>
<p>Like now I don't even remember for that resistance question whether I put only temperature or all three. I remember affirming that temperature does affect it during the test but I don't remember if I carelessly only put down temperature or if I put all of them affected resistance. x.x</p>
<p>I think it was pretty much what i was expecting... except for two unexpectedly tough questions (the galileo one and fractal)</p>
<p>1) Which one is NOT a fractal?
Insect</p>
<p>2) A sheet of metal has a hole in it. When the temperature decreases, the sheet contracts. what happens to the hole?
Hole contracts as well.</p>
<p>3) Two balls are of uniform density. The more massive one falls faster. Why?
Greater mass-to-area ratio</p>
<p>4) Iron at 100 deg C is mixed with water at 20 deg C. The resulting temperature of the mixture is closer to 20 than 100. Why?
Water has a greater specific heat.</p>
<p>5) Light goes through two polaroids. First one has a vertical axis, second horizontal. What is the direction of the light that passes through the second one?
No light passes through.</p>
<p>6) Resistance in wire is affected by:
all of them: area, temperature, and length.</p>
<p>7) What is the magnitude of the electric field in the capacitor below?
I BELIEVE it was V/D, but Im not sure. </p>
<p>9) In which diagram is the net force on the ELECTRON (it was an electron, right?) in the plane of the page and upwards?
Use your right hand rule. The answer is a graph, obviously, so cant really explain it.</p>
<p>10) A light bulb is in a container with no air. Heat is transferred through:
III. Radiation ONLY</p>
<p>11) ___________ _____________
|____<strong><em>| --------d-------->|</em></strong>_______|
which of the following describe the amount of work done?
II. Fd & III. 1/2mv^2</p>
<p>12) The distance from the earth to the moon is 60x the distance the radius of the earth. what is the ratio of the grav. field strength at the moon vs. at the surface of the earth?
3600/1</p>
<p>13) when an object falls it loses what kind of energy?
Gravitational Potential Energy</p>
<p>14) when an electron hits a television screen it loses what kind of energy?
Kinetic Energy - ARE you sure about this?</p>
<p>15) you are underwater and look at a bird above water. where do you see the bird (relative to where the bird actually is)?
Above the surface of the water, above its actual position.</p>
<p>16) (Graph showing this) force of 200 N exerted for 0.1 s. What is the object's change in momentum?
Change in momentum = Ft = 200 * 0.1 = 20kgms</p>
<p>17) Four spaceships traveling at 0.1c, 0.2c, 0.5c, and 0.8c pass by an asteroid. Which one measures the longest length for the asteroid?
The asteroid has the longest length when a person ON the asteroid measures it, not on the spaceships. Answer : the asteroid</p>
<p>18) What did Galileo NOT discover?
The universe is expanding - This is red shift which is modern.</p>
<p>19) Piston problem (pushing/pulling/nothing, adding/taking away heat, or nothing)
I believe it was push piston in and add heat.</p>
<p>20) period of a pendulum is T. what is the new period when its amplitude is doubled?
Amplitude does not affect period, so it would remain T.</p>
<p>21) picture of a wave. at which of the points is the wave moving up?
D, because BCE were at points on the wave where there was no movement and A was at the top of the wave, so it was going down?</p>
<p>22) you have a coil of copper and a magnet. what do you need to do to induce a current in the coil?
Move them relative to each other.</p>
<p>23) when is the potential energy of jupiter the greatest?
When it is furthest away.</p>
<p>I dont actually think this was one of the questions, but it was something along these lines.</p>
<p>24) one plane moves due west; second one due north. what is the direction of the second plane relative to the first one?
Northwest</p>
<p>25) positive charge is shot across a capacitor (top is negative, bottom is positive). what is the path of the charge?
Parabolic towards the negative plate.</p>
<p>26) A beam of light it shot through a small slit. It produces concentric circles on a screen. How can you make the circles on the screen bigger?</p>
<p>Increase wavelength/ smaller slit.</p>
<p>27, 28, and 29) Remember the questions with three graphs. One was of a particle moving in a circle. One was a particle moving in a horizontal direction with acceleration in that direction. One was a particle moving in a horizontal direction w/ accel in an OPPOSITE direction.
Dont remember the questions but it was either II, III, I or III, II, I.</p>
<p>30) 1000 W, 30%</p>
<p>31) The situation that follows the equation X=V x .5(accel)(time-squared) is NOT the frictionless inclined plane. It's the horizontal plane with increasing friction. </p>
<p>Thats all I got for now.</p>
<p>No, with increasing friction means that the net force on the object will change, which means acceleration will not be constant. V_0 + 1/2 a t^2 only works if a is uniform. Thus, it IS the frictionless inclined plane.</p>
<p>anyone can explain the last 2 questions of the test?
the last one was with 3 charges..+ -+...but i dont remember the Q nor the A.
The other one was with a block...but I dont know more..</p>