What is Density? Definition, Meaning & Example
The mass of a substance per unit volume, calculated as mass divided by volume.
TL;DR: The mass of a substance per unit volume, calculated as mass divided by volume.
Written & reviewed by the Syllab.in Academic Team (CBSE/NCERT subject experts) · Updated
Density: The mass of a substance per unit volume, calculated as mass divided by volume.
Explanation
Density indicates how tightly packed the particles of a substance are. Objects with higher density are heavier for their size. Water has a density of 1 gram per milliliter, which is used as a reference standard. Lead is much denser than water, so it sinks, while cork is less dense than water, so it floats. Density varies with temperature; when water is heated, it becomes less dense and expands. Understanding density helps predict whether objects float or sink. In Indian science education, calculating density and understanding its applications is important for Class 8 onwards.
Example
A cubic centimeter of gold has much greater mass than a cubic centimeter of water because gold is denser. Gold sinks while water floats, showing the relationship between density and buoyancy.
Frequently Asked Questions
Why does density affect floating?
Objects less dense than water displace a volume of water equal to their weight, making them float. Denser objects sink.
How does temperature affect density?
As temperature increases, particles move faster and spread apart, usually decreasing density. Cold objects are generally denser.
More Science Terms
🤖 Stuck on any of these? Ask Syllab's free AI Tutor to explain step by step →