Download PDF
;border:1px solid #cccccc;padding:5px 10px;">
LEARNING OBJECTIVES:
By the end of this section, you will be able to:
- Understand the meaning of the term "physical quantity"
- Give examples of physical quantities
- State the correct units of recoring gthe physical quantities
- Convert between different units of physical quantities
So, What is meant by the words " Physical Quantity?"
- Well, A physical quantity is a physical property of a material or a system.
- It is a physical property that can be expressed by measurement.
- A physical quantity can be expressed as a value, which is the algebraic multiplication of a numerical value and a unit.
Examples of physical quantities:
- mass, length, density, velocity, force and length
Units for measuring physical quantities:
When we take measurements of physical quantities , we need to record them in terms of units,These units are standardized values.Below we shall learn about various unist for expressing measurments of physical quantities.
Physical quantity: Length
- Length is a physical quantity that can be expressed in terms of units such as the millimetre, centineter, decimeter, kilometer , hectometre,etc.
- Following is the relation between various units of length:
- (a) 1kilometer=1000millimetres
- (b) 1metre=10 decimetres
- (c) 1metre=100 centimetres
- (d) 1 metre=1000 millimetres
- (e) 1 metre= 0.1 decametres
- (f) 1 metre = 0.01 hectometres
- (g) 1 metre= 0.001 kilometres
Physical quantity: Mass
- Mass is a physical quantity that can be expressed in terms of units such as the milligram, centigram decigram, kilogram , hectogram,etc.
- Following is the relation between various units of length:
- (a) 1kilogram=1000milligram
- (b) 1gram=10 decigrams
- (c) 1gram=100 centigram
- (d) 1 gram=1000 milligrams
- (e) 1 gram= 0.1 decagram
- (f) 1 gram = 0.01 hectograms
- (g) 1 gram= 0.001 kilograms
Physical quantity: Capacity
- Mass is a physical quantity that can be expressed in terms of units such as the millilitre, centilitre, decilitre, kilolitre , hectolitre,etc.
- Following is the relation between various units of capacity:
- (a) 1kilogram=1000milligram
- (b) 1litre=10 decilitre
- (c) 1litre=100 centilitre
- (d) 1 litre=1000 millilitre
- (e) 1 litre= 0.1 decalitre
- (e) 1 litre = 0.01 hectolitre
- (f) 1 litre= 0.001 kilolitres
Physical quantity: Time
- Time is a physical quantity that can be expressed in terms of units such as the hours, minutes, seconds, days etc
- Following is the relation between various units of time:
- (a)1 year =365 days
- (b) 1 day =24 hours
- (c) 1 hour = 60 minutes
- (d) 1 minute= 60 seconds
- (e) 1 second= 1000 milliseconds
- (f) 1 day =86 400 seconds
- (h) 1 hour =3 600 000 milliseconds
Next
Previous
Write a public review