You are Here: Home >< A-levels

# Physics Electric Fields 1 mark question help??? watch

Announcements
1. Attachment 608632

2. what is the question?

what is the question?
I'm trying to upload the picture, can you see it?
4. (Original post by Jas1947)
Attachment 608632

at a distance d, the force between the particles is F. At a distance of 20mm, the force is 0.5F. If you use the equation Force=kQ1Q2/r^2, you should gte 2 expressions for f, one in terms of d. You then just solve for d.
I got an answer of 14mm to 2sf.
5. id say its B because the relationship is an inverse square , so if distance decreases force will increase to 1F which will be at 14mm
6. (Original post by an_atheist)
at a distance d, the force between the particles is F. At a distance of 20mm, the force is 0.5F. If you use the equation Force=kQ1Q2/r^2, you should gte 2 expressions for f, one in terms of d. You then just solve for d.
I got an answer of 14mm to 2sf.
Ah yes! I forgot the squared on the distance. Thanks!!

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: January 5, 2017
Today on TSR

### Exam Jam 2018

Join thousands of students this half term

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

## Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE