Materials and Density

Question 1

What is a linear and non-linear relationship?

Answer 1

If a graph is plotted and the line of best fit is straight then we say that there is a linear relationship between the two quantities on the x and y axes. If the line is not straight then it is non-linear.

Question 2

directly proportional

Answer 2

line of best fit is straight and goes through the origin

Question 3

spring constant

Answer 3

the amount of force needed to stretch or compress an object by 1 metre

Question 4

What is Hooke’s law?

Answer 4

The extension of a material is directly proportional to the force applied up to the limit of proportionality (elastic limit)

Question 5

elastic deformation

Answer 5

if an object returns to its original length after being stretched or compressed without passing the limit of proportionality

Question 6

inelastic deformation

Answer 6

if an object does not return to its original length after being stretched or compressed without passing the limit of proportionality

Question 7

How do you carry out a force extension
experiment accurately?

Answer 7

Set up a clamp stand with a spring. Clamp a ruler, making sure it is vertical with a set square. Make sure the zero of the ruler is at the bottom of the spring. Add masses and record the extension from the ruler each time. Make sure to measure extension at eye level.

Question 8

What do we mean by “uncertainty”
in a measurement?

Answer 8

Uncertainty is the range of values in which we expect the true value of a measurement to lie.

Question 9

When a measurement is repeated, what is the uncertainty in that measurement?

Answer 9

the uncertainty in the measurement is 1⁄2 of the range

Question 10

How can particle arrangement be used to explain the differences in density between solids, liquids, and gasses?

Answer 10

the same volume of a substance in its solid, liquid and gaseous forms then there will be much more space between the particles in a gas than in a liquid or solid. This means that if we had the same volume we would have much less mass of gas. Since density = mass/volume then it follows that the density of a gas is less (since mass is less for an equal volume) than a solid or liquid.

Question 11

Why does density change when a substance changes state?

Answer 11

When a substance changes state, the same mass of substance will now occupy a different volume