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moatasim23
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How can we distinguish scalars from vectors?If we are given a certain physical quantity how can we justify whether it is scalar or vector?
rcremont said:The best example I've found useful is the difference between mass and weight. Mass has no directional value only a magnitude which is a scalar. Weight on the other hand has a magnitude as well as a direction (downward) which is a vector.
Actually they measure the mass not the weight. The fact that they probably measure it with a device that includes a force transducer is no more relevant than whether you measure a length with a wooden ruler or a laser device with a digital readout.the_emi_guy said:They measure the weight of my luggage at the airport because there is a 50lb limit (scalar).
I fly to Singapore (opposite side of the Earth). How much does my luggage weight now? Would you say that its weight is now negative?
AlephZero said:Actually they measure the mass not the weight...
the_emi_guy said:They are measuring weight. "If your bag exceeds weight or size limits, please ..."
Mass can be inferred from weight because we know what planet we are on.
jbriggs444 said:They are measuring mass.
the_emi_guy said:If this apparatus were measuring mass then I could transport it to the moon or deep space and it would give the same reading right?. Scales measure the magnitude of the gravitation force exerted on a body and display that result as a single number that we call weight.
jbriggs444 said:If this apparatus was based on a spring or a load cell and you transported it to the moon without re-calibrating it in its new place of usage, then it would give hugely erroneous results.
DrewD said:I don't think that a citation
"see sign at airport"
would be accepted in a paper and, while this is no peer-reviewed journal, I don't think it should be accepted here.
the_emi_guy said:Exactly my point. This is because it is not measuring mass, it is measuring weight.
A scalar is a physical quantity that has only magnitude, such as mass or temperature. A vector is a physical quantity that has both magnitude and direction, such as velocity or force.
A scalar is represented by a single numerical value with a unit, such as 5 kg or 25°C. A vector is represented by an arrow, where the length represents the magnitude and the direction represents the direction of the quantity.
Some examples of scalars are distance, speed, time, and energy. Some examples of vectors are displacement, velocity, acceleration, and force.
Yes, a vector can be turned into a scalar by finding its magnitude, or the length of the vector. This means that the direction is ignored and only the numerical value and unit are considered.
It is important to distinguish between scalars and vectors in physics because they behave differently in mathematical equations and physical laws. Scalars can be added and subtracted algebraically, while vectors must be added and subtracted using vector addition and subtraction rules. This distinction is crucial in understanding and solving problems in physics.