You are Here: Home >< A-levels

1. *PIC BELOW*

Q1 is for 6 marks, I did Ft=mv-mu then got v to be 11.5m/s. Is this correct?

Q2 is for 8 marks. I did the exact same method and got v = 49.3m/s.

This doesn't make sense? How do I solve these questions

Thanks
2. thanks again!
Attached Images

3. Hey, I'm a current Phyiscs/Maths A2 student- I had a go at both of the questions and I've attached a picture of my workings.

In the first question, I'm sure we both got the same thing so I'm certain it's right. I'm not sure why you would use the impulse equation to solve it because the object isn't colliding with anything- and you learn f=ma and suvat in both physics and m1 maths, so you should be familiar with both. Still, you got the right answer so well done ^_^

The second question I was a bit confused with (and we got different answers), so maybe we can help eachother on that. The main assumption I made was that the impulse of both objects would be the same, but I'm not entirely sure that's true. And if it is, my working seems very short for 8 marks. Let me know what you think about my method!!
4. Small update: I did a quick googl and I found a solution- your answer for Q2 is right!! It looks like my mistake was the double negative. A bit confused about why that's not positive though, since the direction changes, do you have any wisdom on that??

(http://www.jiskha.com/display.cgi?id=1476954557)

Thanks yo!
5. (Original post by sabruh)
Hey, I'm a current Phyiscs/Maths A2 student- I had a go at both of the questions and I've attached a picture of my workings.

In the first question, I'm sure we both got the same thing so I'm certain it's right. I'm not sure why you would use the impulse equation to solve it because the object isn't colliding with anything- and you learn f=ma and suvat in both physics and m1 maths, so you should be familiar with both. Still, you got the right answer so well done ^_^

The second question I was a bit confused with (and we got different answers), so maybe we can help eachother on that. The main assumption I made was that the impulse of both objects would be the same, but I'm not entirely sure that's true. And if it is, my working seems very short for 8 marks. Let me know what you think about my method!!
I do think yours is correct as I forgot to include the extra minus sign, so well done!
6. (Original post by zezno)
I do think yours is correct as I forgot to include the extra minus sign, so well done!
Funnily enough, I posted another post which is currently under review. I googled the question and I found an answer the same as yours. So I don't know if I'm right or not. Here's a pic:

7. (Original post by sabruh)
Funnily enough, I posted another post which is currently under review. I googled the question and I found an answer the same as yours. So I don't know if I'm right or not. Here's a pic:

loool omg I'm so confused.
8. Both of the answers so far look wrong to me.

The screenshot ones have the impulse in the same direction as the initial velocity.

The calculations do some magic with 1.5 that isn't legal!
9. (Original post by RogerOxon)
Both of the answers so far look wrong to me.

The screenshot ones have the impulse in the same direction as the initial velocity.

The calculations do some magic with 1.5 that isn't legal!
I'm sure the first one must be correct no?

the second one I I forgot to add the minus haha
10. (Original post by zezno)
I do think yours is correct as I forgot to include the extra minus sign, so well done!

btw how did you get 50/1.5 as 49.5? lol

I think it should be 50/1.5 - 16 = 17.3m/s
11. (Original post by zezno)
loool omg I'm so confused.
Me too ugh. But I think I'm right- the question specifically said that direction is changed, so there gotta be a double minus there... I think
12. (Original post by zezno)
I'm sure the first one must be correct no?

the second one I I forgot to add the minus haha
The two solutions to the second question look wrong. The first question looks fine.
13. (Original post by sabruh)
The step from 50 = .. to 48.5 = .. looks suspect.
14. (Original post by RogerOxon)
The two solutions to the second question look wrong. The first question looks fine.
Thanks. I believe it should be:

50 = 1.5(v--16)
50 = 1.5(v+16)
v = 50/1.5 - 16 = 17.3m/s

thanks again ( I hope that's right loool)
15. (Original post by zezno)
btw how did you get 50/1.5 as 49.5? lol

I think it should be 50/1.5 - 16 = 17.3m/s
I can't use a calculator lmao, looks like I pressed minus instead of divide. DAS the right answer
16. (Original post by RogerOxon)
The step from 50 = .. to 48.5 = .. looks suspect.
Yeah, I pressed the wrong button on my calculator. Thanks for spotting it!!

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: October 26, 2016
The home of Results and Clearing

### 2,416

people online now

### 1,567,000

students helped last year
Today on TSR

### University open days

1. Keele University
Sun, 19 Aug '18
2. University of Melbourne
Sun, 19 Aug '18
3. Sheffield Hallam University
Tue, 21 Aug '18
Poll

## All the essentials

### Student life: what to expect

What it's really like going to uni

### Essay expert

Learn to write like a pro with our ultimate essay guide.

### Create a study plan

Get your head around what you need to do and when with the study planner tool.

### Resources by subject

Everything from mind maps to class notes.

### Study tips from A* students

Students who got top grades in their A-levels share their secrets