Page 119 - Innovator's Science-8

Determination of Density

The density of an object can be determined by measuring its mass and
volume. How to measure mass?

Mass is the amount of matter present in any object. It tells us how much
stuff or material is inside the object, no matter where it is. To measure
mass, we use a tool called a balance . You might have seen shopkeepers
using different types of balances to weigh things. In science labs, a digital

weighing balance is often used for better accuracy. Mass is different from
weight, though they are related on Earth because weight depends on
gravity acting on the mass. Mass is constant for an object and tells us how
heavy or light the object is based on the amount of matter it

contains.

Activity-2 Aim: To measure the mass of solid object using a Digital
digital weigh ng balance. weighing
Experiential Learning balance
• Switch ON the digital weighing balance.
• Observe the ini al reading on the digital
a. Digital weighing
weighing balance display.
balance
• It should show a zero reading. If not, then we
must bring it to zero by pressing the tare or
Watch
reset bu on glass
• Place a dry and clean watch glass or bu er
paper on the pan.
Science • Note the reading on the digital weighing b. Tare the balance after
Bytes
balance. Reset the digital weighing balance placing a watch glass
Testimony
The digital balance works reading to zero by pressing the tare or reset Stone
on the principle of bu on as shown or solid
electromagne c force • Now, carefully place the solid object, such as object
restora on. When an
stone, on the watch glass
object is placed on the
pan, an electromagne c • Note the reading displayed on the balance, c. Weighing a solid object
coil generates a force which gives the mass of the stone, say 16.400 g. on digital balance
equal to the object's
weight to keep the beam
balance. The strength of The words "mass" and "weight" are often used interchangeably in everyday
this force is converted life, but in science, they have different meanings. Mass is the amount of
into a digital reading of
mass. matter present in an object or substance, and it is measured in grams (g) or
kilograms (kg). Mass remains the same no matter where the object is.

Weight, on the other hand, is the force with which the Earth (or another
planet) pulls an object due to gravity. Weight is measured in newtons (N).
Since weight depends on gravity, it can change if the object is taken to
places with different gravitational forces, like the Moon or outer space, but

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