Chapter 4- Mass, Weight & Density Flashcards
What is weight?
The weight of an object is the gravitational force, or gravity, acting on it. Since weight is a force, its SI unit is newton (N). The direction of weight is towards the center of the earth
What is mass
Mass is the amount of matter in a body. It dose not change with the body’s location or shape. It depends on the number of atoms and molecules that make body. Its SI unit is kilogram (KG)
What is the gravitational field?
A gravitational field is a region in which a mass experience a force due to gravitational attraction. Earth’s gravitational force is strongest at its surface.
What is the gravitational field strength?
Gravitational field strength is defined as the gravitational force acting per unit mass. The weight of an object depends on the gravitational force acting on it.
What is the gravitational field strength on earth and on moon
Gravitation field strength on earth is
10 N/ KG and on moon has 1.6 N/ KG
How are mass and weight related?
The weight or gravitational force acting on an object is dependent on its mass. The more mass an object has, the greater the gravitational force acting on it.
What do common weighing instruments measure?
Instruments like the electronic balance, spring balance and bathroom scale actually measure the weight of an object, not its mass. These machines, however, are calibrated to give readings in grams or kilograms
What is the instrument to measure the mass?
Beam balance
Differentiate between mass and weight.
Mass: Weight:
- an amount of matter. - a gravitational force
- a scalare quantity. - a vector quantity
- SI unit : kilogram (kg). -SI unit : newton (N)
-independent of the gravitational -dependent on the gravitational field
field strength. strength.
-measured with a beam balance -measured with spring balance
or a electric balance.
What is the formula of weight?
Formula for weight is:
Weight = mass x gravity ( W = mg )
Relate gravitational field strength and acceleration of free fall?
The gravitational field strangth at a place in N kg!-1 is the same as acceleration of free fall in ms!-2 experienced at the same place.
What is inertia?
The inertia of an object refers to the reluctance of the object to change its state of rest or motion, due to its mass. An object with a greater mass will have greater inertia. In other words, the larger the mass of an object, the harder it will be for the object to start moving, slow down, move fast or change direction.
What is density?
When we talk about Density, we are talking about how much mass is packed into a given space. The density of a substance is defined as its mass per unit volume. Its SI unit is Kilogram Per Cubic Meter. As most objects we handle daily have relatively small masses and volumes so the the unit Gram Per Cubic Centimetre is used commonly.
how to find out the density?
density = mass/volume
