Multiple Choice (1 Viewer)

RealiseNothing

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1) b
2) d
3) a
4) a
5) d
6) c
7) a
8) d
9) b
10) c
11) b
12) a
13) d
14) b
15) a
16) d
17) b
18) c
19) c
20) a
 

anthony9864

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I don't have the MC sheet can someone post photos or something here so i can post my answers.
 

panda15

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1) b
2) d
3) c
4) a
5) d
6) c
7) a
8) d
9) b
10) c
11) b
12) a
13) d
14) b
15) a
16) d
17) a
18) c
19) c
20) b
 

rx229

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Shouldnt 20 be "d"? Increasing light intensity without changing wavelength should only increase current for both metals, not kinetic energy?????
 

panda15

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Shouldnt 20 be "d"? Increasing light intensity without changing wavelength should only increase current for both metals, not kinetic energy?????
Frequency of the light was under the threshold frequency for Y.
 

RealiseNothing

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Shouldnt 20 be "d"? Increasing light intensity without changing wavelength should only increase current for both metals, not kinetic energy?????
Intensity is related to kinetic energy.

Frequency (hence wavelength) is related to current.
 

rx229

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so it should be "b"? Pretty sure intensity is the number of photons and there is a 1 to 1 interaction between photon and electrons.
 

panda15

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I'm confusing myself atm. Maybe. My head is too gone after that exam.
Hah I know the feel. My brain is fried after three weeks of exams. But I'm pretty sure higher intensity=more photons=more current, but KE stays the same. Hence, it's b)
 

Menomaths

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Hah I know the feel. My brain is fried after three weeks of exams. But I'm pretty sure higher intensity=more photons=more current, but KE stays the same. Hence, it's b)
You're correct
 

RealiseNothing

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Hah I know the feel. My brain is fried after three weeks of exams. But I'm pretty sure higher intensity=more photons=more current, but KE stays the same. Hence, it's b)
Yer you're right.

I'm going to sleep now I think.
 

RealiseNothing

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1) b
2) d
3) c
4) a
5) d
6) c
7) a
8) d
9) b
10) c
11) b
12) a
13) d
14) b
15) a
16) d
17) a
18) c
19) c
20) b
I'm reluctant to say anything after the previous posts, but I got B for 17? It used radial magnets so shouldn't it have a constant torque?

inb4 completely fucking wrong
 

Menomaths

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I'm reluctant to say anything after the previous posts, but I got B for 17? It used radial magnets so shouldn't it have a constant torque?

inb4 completely fucking wrong
I don't know the questions, but I too did put the constant torque one
 

panda15

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I'm reluctant to say anything after the previous posts, but I got B for 17? It used radial magnets so shouldn't it have a constant torque?

inb4 completely fucking wrong
Probably is, I must of missed where it said radial.
 

superSAIyan2

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Quite sure it is constant torque since plane of coil is always parallel to the magnetic field. It cannot be a since the torque doesnt change direction
 
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pls

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I said torque decreases. Wouldn't back emf increase as the motor speeds up, hence decreasing current. Since t=nBIAcosø, torque would decrease?
 

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