Edexcel Physics AS Physics on the Go Unit 1 RETAKE

Scroll to see replies

any sign of an unofficial mark scheme?

Some answers I remember, so if any of these could be confirmed correct, that would be a relief:

vector diagram: 13.4N, 46-47 degrees.

Projectile: 98m

Radius of raindrop: 2.4 x 10^-4m

Max velocity pogo stick: 2.5m/s

Reply 81

pinky.mmnp

I think I got 128J or something less than 130J. I struggled with that question because originally I used 1/2 F deltax. But since I couldn't work it out, I checked the graph for Force applied for the compression of 6 cm and then I used that force in the work done equation (W= fs) with s = 6.

Reply 82

Konanabanana

Original post by BalsamFresh

The radius of drop is correct the projectile distance is correct, i got 40.9 degrees and 18n resultant but i made a mistake on that, also the pogo stick is an ecf but 2.5m/s seems to be the correct answer

Reply 83

pinky.mmnp

Original post by jack.lp.thompson

Do you all think the grade boundaries will be really high because there no y12 doing it but all resits??

Actually I'm doing 1-year a levels so I'm currently taking both my AS and A2 exams so it's not just for resits

Reply 84

pinky.mmnp

Original post by Mizuz

I said that too. I assumed it could not be change in GPE, obviously because one was steel and one was plastic so they must have different change in GPE's??

Yes me too, all the other options involved mass and the mass of the two must be different so I chose same v

Reply 85

Konanabanana

Original post by pinky.mmnp

Actually I'm doing 1-year a levels so I'm currently taking both my AS and A2 exams so it's not just for resits

i think it will be like 54-58 for an A probs closer to 58

Reply 86

Konanabanana

Original post by pinky.mmnp

Yes me too, all the other options involved mass and the mass of the two must be different so I chose same v

answer i put is same velocity because masses cancel anyways

Reply 87

jay_rob

Original post by BalsamFresh

I got all the answers you said apart from the vector diagram. For the Vector diagram I got a magnitude of 25N and i cant remember the angle.

Reply 88

jack456123

Original post by jtebbbs

I wrote about parallax and varying paint levels too, then about temperature again, I thought maybe saying hotter paint => shorter time would be worth a mark or something

I said that its hard to know when to start timing as there's nothing to block up the hole at the bottom of the cup so the liquid just flows out so distorts the final time recorded

Then also said for viscous liquids it'll stick to the sides and not all will pass through the cup so difficult to know when to stop timing and accept that its stuck on the walls of the cup and won't flow out.

How are those points?

Reply 89

AndyB_97

Original post by KINGYusuf

i got 144 too what the hell?!?!?!?!

But it said use the graph

I have done it in a weird way. Basically it said that the spring was compressed by 3cm in the pogo stick, so I used the graphs to get the value of force for 3 cm and than I got the value for force when the extension was 9 cm ( it specified that he has extended it by further 6 cm) I have subtracted the force for 3 cm away from the value I have read off the graph for 9 cm and multiplied it by 0.06 ( W=F * (delta) s ) I got 129J. I think that the mark scheme will have a range of values.

Reply 90

idsjfsiojsdioj

I said the exact same points.

Reply 91

AndyB_97

Original post by KINGYusuf

But isn't the total compression 9cm? 3 and then a further 6

They have specified that they want the work done by the child on the pogo stick. So it is 6 not 9. 3cm was already there

Reply 92

Ppatel0

I got 140 joules and 2.9 for max velocity

Reply 93

Ppatel0

I got 140 joules when I rounded and 2.9 for max velocity anyone else?

Reply 94

idsjfsiojsdioj

Answers so far:
The issue with the paint timer:
It's hard to know when to start timing as there's nothing to block up the hole at the bottom of the cup so the liquid just flows out so distorts the final time recorded.

Then also said for viscous liquids it'll stick to the sides and not all will pass through the cup so difficult to know when to stop timing and accept that its stuck on the walls of the cup and won't flow out.

vector diagram: 13.4N, 46-47 degrees. (I think there will be a range on the mark scheme maybe up to 50 degrees)

Projectile: 98m (around this)

Radius of raindrop: 2.4 x 10^-4m

Max velocity pogo stick: 2.5m/s

Energy transfers on the pogo stick: Elastic strain energy -> Ke+GPE

(edited 7 years ago)

Reply 95

BalsamFresh

for the max velocity of pogo stick. Did people do whatever energy they got (128J, 130J etc) = KE + GPE

I did 128J = GPE + KE.

KE = 128 - GPE

then worked out gpe due to a change in height of 6cm?

Reply 96

T,1996

Original post by KINGYusuf

I GOT 144J aswell BUT MY FRIENDS GOT LIKE 128J? HOW?!?!?!?!?!?!?!?

I did at first, but then I realised it was way too far

Use the graph to get the force when the compression is 6x10^-2
and we know that W= F x S therefore, the force x 6x10^-2 to get 128J

Reply 97

username2636609

Original post by jay_rob

I got all the answers you said apart from the vector diagram. For the Vector diagram I got a magnitude of 25N and i cant remember the angle.

I got around 25N too, not seeing how the majority of people got 13/14N

Reply 98

BalsamFresh

Original post by jtebbbs

Yeah force, kinetic energy and the other one (can't remember) are all dependent on mass, which is different for each ball, velocity is the only one that isn't

velocity is constant and its easy to proof. vacuum, so no air resistance

all GPE goes to KE

mgh = 1/2mv^2

cancel masses

gh = 1/2v^2

v = root(2gh)

since, they were dropped from the same height, velocity will be the same in each case, irrespective of mass.