Lesson 2: Density RP Flashcards
What is density?
- Density is mass per unit volume.
Amount of particles in space
What is the formula for density?
mass/ volume
Give 2 common units for volume.
m³ / cm³
Give the unit for mass.
Kg
exam q may ask for otherwise
What are the 7 steps to the density of irregular solids practical?
1.) Measure mass of object using balance.
2.) Fill eureka can higher than spout and let water flow out (so water is level with spout.)
3.) Hold measuring cylinder below spout.
4.) Place object in eureka can.
5.) Collect water that overflows
6.) Measure the displaced water in measuring cylinder at meniscus.
7.) Use density = mass/ volume
What are regular objects?
- Objects with dimensions that are easy to measure.
What are irregular objects?
- Objects with dimensions that AREN’T easy to measure.
What are the steps of measuring the density of regular objects?
1.) Measure mass of object using mass balance.
2.) Measure the length, width and height using ruler to find volume.
3.) mass/ volume = density
Why do we fill the eureka can higher than the spout.
- To make sure it’s accurate and all water is pushed out when object is placed.
What is the method for finding the density of irregular objects actually called?
- Displacement.
What is the meniscus?
- Meniscus = where the water curves.
q.)
Give 1 source of error that could’ve occurred when student measured volume of rock.
How would this affect the volume of the rock?
- Eye position is above or below meniscus when measuring volume.
- Volume would be higher/ lower than true value.
Q.)
What are the advantages of taking 3 measurements for volume and calculating a mean value? (2)
- Allows anomalies to be identified and ignored.
- Reduces effect of random errors when using equipment.
