Physics - Density and Pressure

Equation for density

Density = mass / volume ρ x m / v

Finding the density of a regular object

• Measure mass w/ electric balance (check for zero error)

• Measure dimensions w/ ruler (measure at eye level)

• Calculate volume

• Repeat and average

• Calculate density = mass / volume

Finding density of an irregular object - Eureka Can

• Measure mass w/ electric balance (check for zero error)

• Repeat and average

• Fill up Eureka Can w/ water until just under spout hole

• Slowly lower object in so water spills out into other cupe

• Measure volume of water in other cup

• Repeat and average

• Calculate density = mass / volume

Finding density of an irregular object - Measuring cylinder

• Measure mass w/ electric balance (check for zero error)

• Repeat and average

• Fil to certain volume

• Gently lower object in water to avoid splashes

• Measure increase in water volume = volume of object

• Repeat and average

• Calculate density = mass / volume

Equation for pressure

pressure = force / area p = F / A

What does pressure at a point in a gas or liquid rest do?

Acts equally in all directions

Equation for pressure difference

Pressure difference = change in height x density x gravitational field strength Δp = Δhρg

Equation for total pressure

Total pressure = pressure difference + atmospheric pressure p = Δp + Patm