WJEC AS Physics PH1 May 19th 2015

1. Horizontal v= 2
Vertical = 2.94
Magnitude = 3.56
Angle = 58
Air resistance to left
2.
3. Pd= 4.5
Pd = 3.75
Combined parallel resistance = 750
Variable resiator = 4500
Pd decreases
4. Experiment....
5.Inave?
6. Zip line..
7.Define displacement -
The displacement of a point B from a point A is the shortest distance from A to B, together with the direction. ( From WJEC definitions.)
Average speed = 48
Average velocity = 0
Thats all i can remember off the top of my head so pretty sure some of those are off

(edited 8 years ago)

Reply 164

gergjre

I PUT LIQUID HELIUM ON THE SUPERCONDUCTIVITY QUESTION AND THEN CHANGED IT TO LIQUID HYDROGEN which has nothing to do with superconductivity. I made so many stupid mistakes and it's probably cost me a huge amount of marks

Reply 165

And I even didn't do the explain resistance in terms of electrons which I'm sure is GCSE, I ran out of time as I attempted to prioritise the big mark questions. And then I heard that some people had like 5 minutes extra to finish off, evil examiner. I didn't want to risk being called a cheater for using more time than permitted :frown:

Reply 166

thegayman

Original post by rhungwilym

it doesn't make sense cause if you travel 600m in total, 40km/h for half and 60km/h for half then you've traveled 50km/h overall right

.........in sorry but that's completely wrong, even in KS2 or KS3 that's just completely wrong,what you e done is find the mean of 60 and 40 as numbers, not the mean VELOCITY, which you can only do by knowing the dostance travelled and the time taken

Reply 167

Original post by gergjre

I PUT LIQUID HELIUM ON THE SUPERCONDUCTIVITY QUESTION AND THEN CHANGED IT TO LIQUID HYDROGEN which has nothing to do with superconductivity. I made so many stupid mistakes and it's probably cost me a huge amount of marks

I hedged my bets by putting both liquid helium and liquid nitrogen... I'm sure I'll get marked for the incorrect one

Reply 168

rhungwilym

Original post by thegayman

.........in sorry but that's completely wrong, even in KS2 or KS3 that's just completely wrong,what you e done is find the mean of 60 and 40 as numbers, not the mean VELOCITY, which you can only do by knowing the dostance travelled and the time taken

I'm sure there will be E.C.F anyways

Reply 169

Original post by sahank1

1. Horizontal v= 2
Vertical = 3.56
Magnitude = 4.1
Angle = 58
2.
3. Pd= 8.5
Pd = 3.75
Combined parallel resistance = 750
Variable resiator = 4500
Pd decreases
4. Experiment....
5.Inave?
6. Zip line..
7.Define displacement - mean velocity x time
Average speed = 48
Average velocity = 0
Thats all i can remember off the top of my head so pretty sure some of those are off

I had different odd to you in q3 (4.5 and 7.5 if I remember correctly) and a completely different answer 1b forward. Probably used the wrong sin or cos and divided instead of multiplied or vice versa. Am I likely to get ecf marks as I only messed up b which effected my later answers? I made a right dogs dinner of moments too *locks room and cries in corner*

Reply 170

Those are completely off the top of my head so you may have got the correct answer and the moments ones were 196, 92 and 58 i think

Original post by DirtyExamTables

I had different odd to you in q3 (4.5 and 7.5 if I remember correctly) and a completely different answer 1b forward. Probably used the wrong sin or cos and divided instead of multiplied or vice versa. Am I likely to get ecf marks as I only messed up b which effected my later answers? I made a right dogs dinner of moments too *locks room and cries in corner*

Reply 171

Qwertykeyboard15

5

Original post by DirtyExamTables

I had different odd to you in q3 (4.5 and 7.5 if I remember correctly) and a completely different answer 1b forward. Probably used the wrong sin or cos and divided instead of multiplied or vice versa. Am I likely to get ecf marks as I only messed up b which effected my later answers? I made a right dogs dinner of moments too *locks room and cries in corner*

I got a different vertical answer on 1b ... Same angle though.. I said the p.d stays the same which I know is wrong but I explained that current would increase and resistance would decrease (I think) so that means that both those changes from V = IxR would cancel out and therefore V would remain the same 😥

Reply 172

Original post by sahank1

Those are completely off the top of my head so you may have got the correct answer and the moments ones were 196, 92 and 58 i think

Oh no, I definitely didn't get it. I stopped when I got to something cos40 as I was unsure of what to do next as I ran out of time

Reply 173

Original post by Qwertykeyboard15

I got a different vertical answer on 1b ... Same angle though.. I said the p.d stays the same which I know is wrong but I explained that current would increase and resistance would decrease (I think) so that means that both those changes from V = IxR would cancel out and therefore V would remain the same 😥

I think you may be right on the pd staying the same

Reply 174

DelAccount123

6

Original post by DirtyExamTables

I hedged my bets by putting both liquid helium and liquid nitrogen... I'm sure I'll get marked for the incorrect one

I put liquid nitrogen but then changed to helium cause I remembered nitrogen only worked for high temp super conductors, I've checked the book and both should be right, played safe and put helium cause it can cool it down to lower temperatures and I wasn't sure if it was above or below liquid nitrogen temperature, was only about 30 degrees above it!

Reply 175

DelAccount123

6

Original post by sahank1

I think you may be right on the pd staying the same

If you're on about the variable resistor question the voltage went down. Basically the R (parallel combo) of the R total went down so V(parallel combo) of the V total went down. The pd of the other resistor went up! Not sure if this explains it very well put if it had 3/4 of resistance it would dissipate 3/4 of pd. If resistance went down by 1 ohm it would have 2/3 of resistance so 2/3 of pd! :smile:

(edited 8 years ago)

Reply 176