ENGR 2102
Vector Mechanics for Engineers
Chapter 1
What is Mechanics?
Mechanics is the science which describes and predicts the
conditions of rest or motion of bodies under the action of forces.
Categories of Mechanics:
- Rigid bodies
- Statics (ENGR-21

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?
What is the direction of
the magnetic field due to
the element ds ?
Direction is into the page
?
If the wire is in the shape of a circle of radius R
What is the
angle in this
case?
If the wire is in the shape of a circle of radius R
Magnetic field at

We want to find the magnetic field at point P due to the straight
finite wire with current
P
I
What is the direction of the magnetic field at P due to the element
of length shown?
y
P
r
x
ds
I
What is the direction of the magnetic field at P due to the el