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GCSE Edexcel physics - 12th June 2014

What did everyone think of the paper? I wasn't sure about the ice rink question or the 14000N rope question when the car has a weight of 12000N ( can't remember the exact numbers)
Thanks
:smile:

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Reply 1

TheSweatyNerd

Easiest paper I have done in my life, I will get 100% raw marks, as per usual.

Reply 2

Eradicating

Original post by TheSweatyNerd

Easiest paper I have done in my life, I will get 100% raw marks, as per usual.

Ikr! What did you get for current? Calculation. .

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Reply 3

Eradicating

Original post by huwgerard

What did everyone think of the paper? I wasn't sure about the ice rink question or the 14000N rope question when the car has a weight of 12000N ( can't remember the exact numbers)
Thanks
:smile:

The rope has 12000N

Whilst the car has 14000N.

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Reply 4

luuuucian

For the car and rope one I said it wouldn't snap because weight is a vertical force, the only thing which would affect the tension of the rope would be a horizontal force like the drag of the car.

Reply 5

TheSweatyNerd

Original post by Eradicating

Ikr! What did you get for current? Calculation. .

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5.83 or 7.83 I think.

Reply 6

Eradicating

Original post by jhjamie

For the car and rope one I said it wouldn't snap because weight is a vertical force, the only thing which would affect the tension of the rope would be a horizontal force like the drag of the car.

I wrote it will snap because as the velocity is constant, the car is pulling the truck back by its drag by 14000N. Thus the truck will have exert a equal but opposite force and thus the truck will have 14000N to opposite direction. The rope will break as tension is applied because it has a force of 12000N.

(edited 9 years ago)

Reply 7

Eradicating

Original post by TheSweatyNerd

5.83 or 7.83 I think.

It wad 7.7.... round it up to 7 8

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Reply 8

luuuucian

Original post by Eradicating

I wrote it will snap because as the velocity is constant, the car is pushing the truck back by its drag by 14000N. Thus the truck will have exert a equal but opposite force (<--) thus will be 14000N. This will mean that tension will applied to the rope and will split as it has less force then both the directions of the car (drag) and truck.

Dunno I guessed that one.

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I'm not sure, I asked my teacher about it and told him my answer and he said I was correct? I could be wrong though.

Reply 9

TheSweatyNerd

Original post by Eradicating

It wad 7.7.... round it up to 7 8

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Yeh 7.8

Reply 10

luuuucian

If the velocity is constant and all forces are in balance then surely the rope can't snap? It will only snap if there's a resultant force, no?

Reply 11

Akashi

The rope will not snap. It will be able to tow the car. I had a 5.83 answer somewhere.

Reply 12

Eradicating

Original post by Akashi

The rope will not snap. It will be able to tow the car. I had a 5.83 answer somewhere.

5.8? For what. .

It was 7.8

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Reply 13

Akashi

Original post by Eradicating

5.8? For what. .

It was 7.8

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I can't remember if the question was how long did it take for the acceleration to take. It was something like 20-13/something. What was the current question?

Reply 14

Eradicating

Original post by Akashi

I can't remember if the question was how long did it take for the acceleration to take. It was something like 20-13/something. What was the current question?

It was rearranging the acceleration formula

T= 20-13 × (... I forgot.

Current =power/voltage

It was 7.8 :biggrin:

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20-13/T = 1.2 right?

Original post by Akashi

20-13/T = 1.2 right?

you had to find time.

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Reply 17

Akashi

Original post by Eradicating

you had to find time.

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Yep. 1.2 = 20-13/T so 1.2 x t = 20-13. 20-13/1.2 = T. T = 5.83

Reply 18

Eradicating

Original post by Akashi

Yep. 1.2 = 20-13/T so 1.2 x t = 20-13. 20-13/1.2 = T. T = 5.83

I don't remember doing that or getting that answer.

Most people rearranged the acceleration formula (v-u/t) to make t the object.

T= v-u × A

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Reply 19

Akashi

Original post by Eradicating

I don't remember doing that or getting that answer.

Most people rearranged the acceleration formula (v-u/t) to make t the object.

T= v-u × A

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A = v-u/T. You can't just do A x v-u because v-u isn't dividing - it is being divided. Therefore, its reciprocal is not to just multiply it out.
The numbers were 1.2 = 20-13/T. Using your method T would = 8.4. Insert it into the first equation (A = v-u/t). 1.2=7/8.4. It doesn't work.