# Homework Help: Physics Baisic Lab Question and Scalar Components

1. Aug 29, 2006

### chs1491

Hey!
New to this site, started taking physics yesterday and already need some help

1)My textbook is very complicated, is there an easy way that anyone can explain what scalar components are?

2)I did a lab with a force table and 3 pulleys. You add weight to one pully to even out a ring. I'm sure plenty of you have done this before. If you have, could you explain to me how you measure in that lab...thanks.

Thanks for any help I may recieve!

2. Aug 30, 2006

### andrevdh

Well, first there are things that are called vectors. We use vectors in physics to represent physical quantities were both the size and direction of the quantity is important. For instance if you ride your bicycle around in your neighbourhood with a walkie-talkie it would be nice to know your range from base. Vector algebra can be of help here. That is there exist a body of maths that tells us how to manipulate such vector quantities to get what we want. So vectors are defined by their direction (an angle with respect to some fixed direction) and their size. Vector algebra can be simplified if we decompose vectors into their scalar components. We then do the maths with these components to get the results. If the vector is in two dimensions (a flat plane) then each vector is defined by two components. These components are the lenghts of the vectors along a rectangular coordinate system. So in such a x-y coordinate system the vector has two scalar coordinates each with a positive or negative size depending on in which direction the vector is pointing with respect to the coordinate system. One of the components can be zero if the vector lies along one of the axes of the coordinate system. A single vector can have several scalar components, depending on which coordinate system we choose, that is we can rotate the coordinate system to a new direction and the vector will have some other components in the rotated system.

3. Aug 30, 2006

### POSITION_VECTOR

same dimension

in a coordinate system, a 1 and 2 on the x coordinate are scalar components of the vector on the x coordinate with magnitudes of 1 and 2. so, basically, a scalar component of a vector is the absolute value of the magnitude of that vector.

we can do many things with scalar components as long as some rules are met. these rules describe how the philosophy of numbers work.