# Electric Fields Calculation Specimen Paper 2 AQAWatch

Announcements
#1
An α particle makes a head-on collision with a gold nucleus containing 79 protons. The distance of closest approach of the α particle to the nucleus is 4.0 × 10^−14 m.
What electrostatic force acts on the gold nucleus when at this separation?

A) 9.1 × 10^−11 N
B) 23 N
C) 290 N
D) 1.4 × 10^20 N
0
4 weeks ago
#2
Use the equation for the force between two point charges, what are the charges on the nucleus and alpha particle?
0
#3
yeah i did that, keep getting B which isn't right
(Original post by justsomeguy17)
Use the equation for the force between two point charges, what are the charges on the nucleus and alpha particle?
0
4 weeks ago
#4
post ur workings
0
4 weeks ago
#5
23N is the correct answer, the mark scheme is wrong.
0
#6
100% sure yeah?
my workings
F=(1/(4Pi*8.85x10^-12)) * (79x(1.6x10^-19)*2(1.6x10^-19)/(4x10^-14)^2)
=23N
(Original post by justsomeguy17)
23N is the correct answer, the mark scheme is wrong.
0
4 weeks ago
#7
Yeah it's a specimen paper so they'll be a few mistakes. I've seen videos on youtube of people solving this question and they get the same answer 23N, I've also asked my physics teachers and they get 23N as well. Rest assured :P
(Original post by mahmed69)
100% sure yeah?
my workings
F=(1/(4Pi*8.85x10^-12)) * (79x(1.6x10^-19)*2(1.6x10^-19)/(4x10^-14)^2)
=23N
0
#8
ah i seee i did the rest of the paper as well, some of the questions/answers are such nonsense. Just sums up AQA I guess

any predictions for tomorrow?
(Original post by justsomeguy17)
Yeah it's a specimen paper so they'll be a few mistakes. I've seen videos on youtube of people solving this question and they get the same answer 23N, I've also asked my physics teachers and they get 23N as well. Rest assured :P
0
X

new posts
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### University open days

• University of Warwick
Fri, 21 Jun '19
• University of Bath
Find out about life at the University and discover our diverse range of Undergraduate courses. Our course areas include the Sciences, Humanities & Social Sciences, Engineering & Design, and Management. Undergraduate
Fri, 21 Jun '19
• University of Liverpool
Fri, 21 Jun '19

### Poll

Join the discussion

#### How did your AQA A-level Chemistry Paper 3 go?

Loved the paper - Feeling positive (289)
31.86%
The paper was reasonable (436)
48.07%
Not feeling great about that exam... (109)
12.02%
It was TERRIBLE (73)
8.05%

View All
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.