WJEC Physics PH1 20th May 2014

Scroll to see replies

Wait, last year you needed 70/80 for an A???!!!???

For the Hooke's law one, I wrote the extension is halved as the force is shared between the 2 springs but k is the same, and that EPE is the same cos both springs have half the EPE from before, so total is the same.

Posted from TSR Mobile

Reply 22

Shre142

Yes I got A for the aeroplane one.

Posted from TSR Mobile

Reply 23

fridie3000

Original post by manjot97

Anyone else choose "A" for the aeroplane question?

Yeah. What did you get for the resultant velocity when it hit the ground?
i got 71 m/s

(edited 9 years ago)

Reply 24

manjot97

Original post by fridie3000

Yeah. What did you get for the resultant velocity it hit the ground at?
i got 71 m/s

I dont recall getting 71. But then again you may be right..

Reply 25

Wiggledinho

Original post by manjot97

Anyone else choose "A" for the aeroplane question?

me... *please be right*

Reply 26

Shre142

I also got 71, but did you have to write it hits at an angle of 25°?
It was just Pythagoras.

Posted from TSR Mobile

Reply 27

fridie3000

Original post by Shre142

I also got 71, but did you have to write it hits at an angle of 25°?
It was just Pythagoras.

Posted from TSR Mobile

no you didnt need the angle. it was just the 65^2 + the vertical componant^2 all sqaure rooted

Reply 28

manjot97

The resistance length and resistivity question was really easy. Anyone agree?

Reply 29

Shre142

Original post by manjot97

The resistance length and resistivity question was really easy. Anyone agree?

Yeah thought the majority of the paper was quite easy, only found Hooke's law one a bit tricky.

Posted from TSR Mobile

Reply 30

fridie3000

Time to start ph2 revision

Reply 31

Wiggledinho

Original post by fridie3000

Yeah i think that's what i got and for the spring one i think the extension is halved but the total potential energy is the same

thats exactly what I put :biggrin:

Reply 32

minibuttons

Original post by Shre142

Yes I got A for the aeroplane one.

Posted from TSR Mobile

Damn I put B :/ How did you get it to be A? I can't visualise it.

(edited 9 years ago)

Reply 33

Wiggledinho

Original post by fridie3000

no you didnt need the angle. it was just the 65^2 + the vertical componant^2 all sqaure rooted

I think you did need the angle, seeing as its a vector so has direction as well

Reply 34

Shre142

Original post by minibuttons

Damn I put B :/ How did you get it to be A? I can't visualise it.

Because it travels at 65ms-1 in the horizontal and accelerates from rest in the vertical, so it can't be B (because in that one, it has no horizontal) and can't be C because its backwards. Watch a video about the blitz.. You'll see the bombs dropping in that way. Also if it was be, the resultant velocity would just be 30.. So there isn't much point in giving that question. :smile:

Posted from TSR Mobile

Reply 35

Shre142

Original post by Wiggledinho

I think you did need the angle, seeing as its a vector so has direction as well

Yeah I put the angle in anyway, just to be sure

Posted from TSR Mobile

Reply 36

bob321

It is A as it had an initial velocity of 65ms-1 so would accelerate forwards.

Reply 37

rb96

What did people get for the drift velocity?

Reply 38

WayBeyondBlue_

For the question where they added another spring, you had to realise that this is springs in 'parallel', meaning they share the extension, so extension is halved. Then, as extension squared is proportional to EPE, the EPE is decreased by a factor of 4 in each string, so the total EPE is half the original value of 0.036J.

Posted from TSR Mobile

Reply 39

buttered_peanut

Original post by Wiggledinho

Wait, last year you needed 70/80 for an A???!!!???

In Jan 2014 it was 61/80 for an A because in Wales they still have January modules. Don't know if that changes anything. I'm in England so sitting PH1 and 2 now.