Calculating the density of regularly shaped objects
Density = mass/volume
Measure mass using a balance
Measure the dimensions of the object using an appropriate measuring device (e.g. ruler)
Repeat and take an average
Calculating the density of irregularly shaped objects:
Density = mass/volume
Measure mass using a balance
Add the object to water in either a measuring cylinder of known volume or a displacement can
Measure the volume of displaced water using a measuring cylinder from the bottom of the minescus
Repeat and take an average
pressure = force/area
If a fluid (gas or liquid) is not in flow then the pressure at a point in the fluid acts equally in all directions. This is not true if the fluid is moving or is in flow.
If you were asked to represent the pressure on a point in a gas then you must draw force arrows so that the overall sum of the forces is zero.
pressure difference = density * g * height
Explain how the force due to the air pressure inside the cabin on the small window differs from the force on the larger window.
Force is less on small window, pressure is the same.
Explain how a student could measure the volume of a piece of irregularly shaped copper.
Use a measuring cylinder/beaker or use a eureka can/displacement can/container with spout
Fill measuring cylinder/beaker with water and note the reading or fill can to spout
Immerse piece of copper in water
Note difference in readings of water level or collect water from spout in a measuring cylinder/beaker
