Electric & Magnetic Forces — Drills · Grade 8 Science
Chapter: ForcesWhat these drills covers
By the end of Electric & Magnetic Forces you should be able to:
- I can use a field model to describe forces between objects that are not touching.
- I can design a fair test of how magnet separation affects its interaction with another object.
- I can interpret coil-strength records and model stored energy in changed field arrangements.
6 questions, written answer and multiple choice, each with a worked explanation.
Vocabulary used: field, repel, controlled variable, model, evidence, system boundary, assumption, electric charge, polarization, current, coil, electromagnet, compass.
Problem 1
Answer and explanation
To see whether the pattern is consistent and reduce the effect of random variation.
Problem 2
- repel
- attract
- always vanish
- have no interaction
Answer and explanation
attract
Unlike charges attract.
Problem 3
- attract
- repel
- do nothing
- become neutral
Answer and explanation
repel
Like poles repel; unlike poles attract.
Problem 4
- are always stronger
- act without the objects touching
- only act on metals
- require motion
Answer and explanation
act without the objects touching
They are non-contact forces, acting through a field across a distance.
Problem 5
- attract
- repel
- not interact
- neutralise instantly
Answer and explanation
repel
Like charges repel, as like magnetic poles do.
Problem 6
Answer and explanation
A field is a region in which an object would experience a force without anything touching it. The idea is useful because it lets you describe the strength and direction of the force at every point in space before a second object is even placed there, which explains how one object can affect another across a gap.
Response criteria
- State a scientifically accurate conclusion.
- Show the data, mechanism, or calculation that supports it.
- Include units, conditions, or limits where relevant.