How do you measure density of an irregula solid by using Eureka can?

Explain how would you measure density of an irregular solid using a Eureka can.

How do you measure density of a gas?

How do you measure work done?

How do you measure density of a liquid using a graduated measuring cylinder?

How do you measure density of a liquid using a density bottle?

Explain how to find the density of an irregular solid, say a stone.

How can you determine the volume of an irregular solid (say a piece of brass) ? Describe in steps with neat diagrams.

How can you decrease the average density of an object?

How do you identify nature of charge on a charged body using an electroscope?

How do you measure the time period of a given pendulum? Why do you note the time for more than one oscillation?