MedVision ad

Multiple Choice (1 Viewer)

RealiseNothing

what is that?It is Cowpea
Joined
Jul 10, 2011
Messages
4,591
Location
Sydney
Gender
Male
HSC
2013
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

New Member
Joined
Feb 7, 2012
Messages
15
Gender
Male
HSC
2013
I don't have the MC sheet can someone post photos or something here so i can post my answers.
 

panda15

Alligator Navigator
Joined
Feb 22, 2012
Messages
675
Gender
Male
HSC
2013
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

I eat babies
Joined
Apr 14, 2012
Messages
3
Location
Ursa Major II Dwarf
Gender
Undisclosed
HSC
2013
Uni Grad
2004
Shouldnt 20 be "d"? Increasing light intensity without changing wavelength should only increase current for both metals, not kinetic energy?????
 

panda15

Alligator Navigator
Joined
Feb 22, 2012
Messages
675
Gender
Male
HSC
2013
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

what is that?It is Cowpea
Joined
Jul 10, 2011
Messages
4,591
Location
Sydney
Gender
Male
HSC
2013
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

I eat babies
Joined
Apr 14, 2012
Messages
3
Location
Ursa Major II Dwarf
Gender
Undisclosed
HSC
2013
Uni Grad
2004
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

Alligator Navigator
Joined
Feb 22, 2012
Messages
675
Gender
Male
HSC
2013
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

Exaı̸̸̸̸̸̸̸̸lted Member
Joined
Jul 9, 2013
Messages
2,373
Gender
Male
HSC
2013
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

what is that?It is Cowpea
Joined
Jul 10, 2011
Messages
4,591
Location
Sydney
Gender
Male
HSC
2013
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

what is that?It is Cowpea
Joined
Jul 10, 2011
Messages
4,591
Location
Sydney
Gender
Male
HSC
2013
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

Exaı̸̸̸̸̸̸̸̸lted Member
Joined
Jul 9, 2013
Messages
2,373
Gender
Male
HSC
2013
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

Alligator Navigator
Joined
Feb 22, 2012
Messages
675
Gender
Male
HSC
2013
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

Member
Joined
Apr 18, 2012
Messages
320
Gender
Male
HSC
2013
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
 
Last edited:

pls

New Member
Joined
May 27, 2013
Messages
8
Gender
Male
HSC
2013
I said torque decreases. Wouldn't back emf increase as the motor speeds up, hence decreasing current. Since t=nBIAcosø, torque would decrease?
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top