imported_corcoran_chris

Hey guys im stuck on this question, im taking an earth and space science course adn they want to know the answere to this

Why is the unit Newton a more appropriate measurement for the weight of an object as compared to the standard units of kilograms and pounds that you see on your bathroom scale?

imported_jj2ii3344

I cannot verify this but I think the kilograms or the pounds you see on your bathroom scale varies depending on its distance from the center of the Earth.

imported_Bruce Fee

mass is the universal measurement.

weight will change depending on the gravitational pull.

Your weight for example will change if you are on the moon, earth, or mars.

Your mass will remain the same.

The top and bottom of a mountain, will also provide different measurements of your weight, but not by much.

This doesn't matter really for a chick checking to see if the Tae Bo is working, but is important for things that matter where precision is vital.

Do a couple searches on google, you should find some good resources.

imported_corcoran_chris

yeah its alongt those lines I belive, im not too sure how to word it all or the right answere
I know newtons is a measure of force on an object..so its constant and its more acurate then just regular measurements of mass be it lbs/pounds or kilograms...but why

imported_corcoran_chris

so the newton form of measurement is more accurate because....

imported_Bruce Fee

Mass vs. Weight

The force of gravity is a source of much confusion to many students of physics. The mass of an object refers to the amount of matter that is contained by the object; the weight of an object is the force of gravity acting upon that object. Mass is related to "how much stuff is there" and weight is related to the pull of the Earth (or any other planet) upon that stuff.

The mass of an object (measured in kg) will be the same no matter where in the universe that object is located. Mass is never altered by location, the pull of gravity, speed or even the existence of other forces. For example, a 2-kg object will have a mass of 2 kg whether it is located on Earth, on the moon, or on Jupiter; its mass will be 2 kg whether it is moving or not (at least for purposes of this study); and its mass will be 2 kg whether it is being pushed or not.

On the other hand, the weight of an object (measured in Newtons) will vary according to where in the universe the object is. Weight depends upon which planet is exerting the force and the distance the object is from the planet. Weight, being equivalent to the force of gravity, is dependent upon the value of g (acceleration of gravity). On Earth's surface, g is 9.8 m/s2 (often approximated to 10 m/s2). On the moon's surface, g is 1.7 m/s2. Go to another planet, and there will be another g value. In addition, the g value is inversely proportional to the distance from the center of the planet. So if g were measured at a distance of 400 km above the earth's surface, you would find the value of g to be less than 9.8 m/s2. (The nature of the force of gravity will be discussed in detail in Unit 6 of The Physics Classroom.) Always be cautious of the distinction between mass and weight. It is the source of much confusion for many students of physics.

You must thoroughly understand the meaning of each of these forces if you are to successfully proceed through this unit. Ultimately, you must be capable of reading the description of a physical situation and knowing enough about these forces to recognize their presence (or absence) and to construct a free-body diagram which illustrates their relative magnitudes and directions.

taken from
http://www.physicsclassroom.com/Class/newtlaws/u2l2b.html

imported_Bruce Fee

I just did a search on google, got that and a bunch of other sites.

mass vs weight

imported_corcoran_chris

thanks bruce, helped me out big time...do you have MSN? hahah may need to ask you a few more things if you are interested....
add me
sk8ter_2000@hotmail.com

imported_viper_2_4

yup, just like bruce said, there is a difference between mass and weight......newtons would be the effect of gravity (isn't it mass*acceleration due to gravity (which on earth is 9.8m/s^2))

imported_Bruce Fee

viper, yeah, that's the equation for the acceleration of a falling object.... or the velocity.. something like that... it's been a while for me.

QuiCK_TiME

chris, if u need math or phys help, gimmie a shout on msn.

regards,
damian

bbarbulo

iTrader: (2)

kg and lbs are only accurte on earth. like in an elevator, scales are far from accurate. that's the simple way to put it.... but Mr. Fee's got you covered