Can't we say vector or scalar quantity is relative thing

In summary, the conversation discusses the concept of vector and scalar quantities and how they are used to express physical quantities. The speakers point out that some quantities, such as area and pressure, can be considered both scalar and vector depending on the context. However, the argument is made that these quantities are not truly relative, but rather arbitrary and described by a vector with unnecessary information removed for convenience.
  • #1
samieee
67
0
Can't we say vector or scalar quantity is relative thing!

We all know that physical quantities are expressed as vector or scalar quantities.Now let consider 'area',if I say my house is 2000 sq.feet in that sense area may be called scalar but area of a surface is a vector quantity[either upward or downward direction].Now another example is pressure.It is much debatable whether pressure is scalar or vector.So we can solve the dilemma by saying that the whole thing is relative,don't we?
 
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  • #2


The 'area' is a scalar. The specific shape of some square is a vector. Saying "2000 square feet" loses information as to whether it is long or skinny, or golden ratio, or square; as well as which direction is normal to that floor plan.
 
  • #3


yes area is scalar but some specific cases it is vector[area of surface or plane] so can't we call it relative thing?
 
  • #4


Ever heard of tensors? The world is not completely described by scalars and vectors alone.

Your point is somewhat moot, because the same applies with speed and velocity. When we don't care about direction, it suffices to simply use speed, as in 1/2 m v^2. Similarly, when we don't care about the orientation of a given surface, we can simply use its area, without a specified normal vector. The exact same thing applies for pressure. It's not relative, and in a sense you could argue that these quantities are fully described by a vector and we merely chop off the unnecessary information (make them scalars) when it is convenient for us. But it's certainly not relative. What it is is arbitrary, since for a given surface the choice of normals is completely by convention. It's really not a dilemma at all.
 
  • #5


I would say that while it is true that the classification of a physical quantity as a vector or scalar can be relative, the underlying nature of the quantity itself is not. A vector quantity has both magnitude and direction, while a scalar quantity only has magnitude. This distinction remains the same regardless of how we choose to classify or measure the quantity.

In the case of area, while the concept of a surface having an upward or downward direction may be relative, the actual area itself is still a vector quantity because it has both magnitude (in terms of square feet) and direction (upward or downward). Similarly, the pressure may be debatable as to whether it is a vector or scalar, but its underlying nature as a force per unit area remains the same.

In science, we strive to understand and quantify the physical world around us. While the classification of vector and scalar quantities may be relative, the fundamental properties and characteristics of the quantities themselves are not. Therefore, it is important to accurately classify and measure these quantities in order to fully understand and describe the physical phenomena they represent.
 

1. Can a vector or scalar quantity be considered a relative thing?

Yes, a vector or scalar quantity can be considered a relative thing because its value may change depending on the frame of reference or the observer's perspective.

2. How is a vector quantity different from a scalar quantity?

A vector quantity has both magnitude and direction, while a scalar quantity only has magnitude.

3. Are there any real-life examples of vector and scalar quantities?

Yes, there are many real-life examples of vector and scalar quantities. Velocity, force, and acceleration are all examples of vector quantities, while mass, temperature, and time are examples of scalar quantities.

4. Can a vector quantity be converted into a scalar quantity?

No, a vector quantity cannot be directly converted into a scalar quantity because they represent different physical properties. However, some vector quantities can be broken down into their scalar components.

5. How does the concept of relativity apply to vector and scalar quantities?

The concept of relativity applies to vector and scalar quantities because their values can vary depending on the observer's frame of reference. This is a fundamental principle in physics, as it allows us to understand and explain the behavior of objects in different situations.

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