Understanding Vector and Scalar Quantities in Physics

In summary, scalar quantities are those that have only magnitude while vector quantities have both magnitude and direction. When solving for scalar quantities, a +/- sign is used to indicate the direction of the field. This is done by leaving the answer as is or using the magnitude for calculations. In contrast, vectors are defined by magnitude and direction, with +ve indicating the same direction as the vector arrow points. The use of a - sign in front of a vector answer indicates the direction is opposite to the direction of the vector arrow. This concept can be applied to understanding the direction of movement in a car with a velocity of -5 m/s to the right.
  • #1
Rawr
15
0
No, I am not going to ask you what the difference between those two are. =P

I know the differences, but at the beginning of this term, my class started to learn about electricity and magnets, and that stuff.

Now, vector quantities are those that have direction and scalars are those without directions.

But then my teacher says... to put a +/- in front of an answer if it is a scalar quantity and to not put anything in front of an answer if it is a vector quantity.

What the heck? That really threw me off.

Could someone clarify on why we need to do that please? @_@
 
Physics news on Phys.org
  • #2
put a +/- in front of an answer if it is a scalar quantity and to not put anything in front of an answer if it is a vector quantity.

Can you put that into context?
 
  • #3
I think your teacher means to leave the answer as is to indicate the direction of the field. Or to know what the direction is and to use the magnitude for the calculations.
 
  • #4
What are the difference between scalar and a vector quantity
 
  • #6
your teacher put plus and minus sign to indicate directions...
if you going to put it in the cartesian plane it will have the positive and negative value of "x" or "y".
 
  • #7
If a vector is defined by magnitude and direction, +ve is defined as in the same direction as the vector arrow points. What does putting a - in front do?
Well, in what direction would do you say a car is moving if it is traveling at a velocity of -5 m/s to the right?
 

What is the difference between a vector and a scalar quantity?

A vector quantity has both magnitude (size or amount) and direction, while a scalar quantity only has magnitude.

How are vector quantities represented graphically?

Vector quantities are represented by arrows, where the length of the arrow represents the magnitude and the direction of the arrow represents the direction of the quantity.

What are some examples of vector quantities?

Examples of vector quantities include displacement, velocity, acceleration, force, and momentum.

How are scalar quantities represented graphically?

Scalar quantities are represented by numbers or symbols, without any direction. They can also be represented by a single point on a graph.

What are some examples of scalar quantities?

Examples of scalar quantities include mass, temperature, time, distance, speed, and energy.

Similar threads

  • Introductory Physics Homework Help
2
Replies
44
Views
2K
  • Introductory Physics Homework Help
Replies
13
Views
522
Replies
17
Views
386
  • Introductory Physics Homework Help
Replies
1
Views
3K
  • Thermodynamics
2
Replies
35
Views
3K
Replies
15
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
3K
  • Introductory Physics Homework Help
Replies
8
Views
1K
Replies
6
Views
6K
  • Classical Physics
Replies
11
Views
3K
Back
Top