Length is measured by using a ruler also known as scale.

• The period of one oscillation can be measured by measuring the time for 20 oscillations and then dividing the time by 20.

• The volume of a cube or cuboid can be found by measuring the length of the three sides and multiplying the measurements together.

• The volume of a liquid can be measured using a measuring cylinder where the bottom of the meniscus appears on the scale when looked at horizontally.

• The volume of an irregularly shaped object can be found from the change in the height of liquid in a measuring cylinder when it is immersed in the liquid.

• Density is the ratio of mass to volume for a substance: ρ=m/v.

• Anything less dense than water will float in water and anything denser than water will sink in water.

• Ice floats because it is less dense than water and one liquid will float on top of another liquid if it is less dense.

Questions

1. Three metal cubes have the same volume but are made of different metals. Each one is lowered into a beaker of water. Use the data in the table to decide which one will cause the biggest rise in water level.

2. gold

3. silver

4. lead

5. all will cause the same rise in water level

( Answer ) 1

Ans ) Gold

2. Three metal cubes have the same mass but are made of different metals. Each one is lowered into a beaker of water. Use the data in the table to decide which one will cause the biggest rise in water level.

1. gold

2. silver

3. lead

4. all will cause the same rise in water level

( Answer ) 2

Ans ) all will cause the same rise in water level

3)

Astronauts land on another planet and measure the density of the atmosphere on the planet surface. They measure the mass of a 500 cm3 conical flask plus stopper as 457.23 g. After removing the air, the mass is 456.43 g (1 m3 = 1000 litres). What is the best estimate of the density of the air?

Ans ) 0.0016 kg/m cube

4 ) The graph shows the mass and volume of several different objects.

Questions : Which two objects have the same density?

2 and 3 as lets say we have on mass side 1 and 2 and on volume side 1 and 2. 1/1 is