Hi im currently studying A-level physics and am having trouble understanding the concepts of these diagrams. I get really confused, and all i can remember is that there must be equal and opposite forces using Newton 3.
2007-01-19 07:35:54 · 4 answers · asked by matt v 1 in Science & Mathematics ➔ Physics
No, its not really about Newton's third law really.
You draw all the forces on a body.
If the body is at rest or in constant motion (as in most statics problems), the vector sum of all the forces must be zero. (More Newton's first law)
If the vector sum is zero, then the components in each direction (say x, y, and/or z) must be zero.
They usually give you enough information to draw the vectors and solve a system of equations (1 equation for setting each component to zero) for every missing variable.
Make sense?
2007-01-19 07:45:23 · answer #1 · answered by Anonymous · 0⤊ 0⤋
FBD's are just a picture showing the forces acting on an object in vectors.
the sum of the forces = 0 (static motion or no motion)
or
the sum of the forces = m*a
forces and acceleration are vectored quatities so look out!
sum of the forces in the x-direction = m*accel in the x direction
sum of the forces in the y-direction = m*accel in the y direction
2007-01-19 07:49:36 · answer #2 · answered by Anonymous · 0⤊ 0⤋
No such thing
Force diagrams must have closure.
2007-01-20 01:35:57 · answer #3 · answered by Anonymous · 0⤊ 0⤋
yes..thats what I thought when I read your question. Then I realised I didn't really understand what you were talking about...
2007-01-19 07:40:36 · answer #4 · answered by welchy56 2 · 0⤊ 0⤋