2. EQUILIBRIUM
•State of body in which it is moving with
constant velocity or in static. Under the action
of many forces.
•We can say that if acceleration is zero(a=0)
than body is in equilibrium.
Now we will discuss its types:
There are two types of equilibrium
i. Static
ii. Dynamic
Static equilibrium:
“a body is said to be in static equilibrium if it
is at rest means it is stable in at a
3. EXAMPLE:
A book is lying on a table etc.
DYNAMIC EQUILIBRIUM:
It is defined as:
“when a body is moving with costant velocity
then we can say that is in dynamic equilibrium”
EXAMPLE:
A car moving with uniform velocity under the
action of many forces.
The dynamic equilibrium is further divided
into two types:
•Translational equilibrium.
•Angular equilibrium.
4. Translational equilibrium:
a body is said to be in translational if it is
moving in (x,y) direction with constant acceleration.
V= constant.
a=0.
Rotational equilibrium:
if a body is moving with constant
angular velocity then it is rotational equilibrium.
e.g. rotation of earth around the sun in 24 hours.
5. CONDITIONS FOR EQUILIBRIUM:
Following are the two conditions of
equilibrium on following which we can say
that a body is in equilibrium:
• the sum of all forces are equal to zero
∑ Fx=0 ; ∑ Fy=0 ; ∑F=0
• the sum of all torque or moment of forces
is equal to zero.
∑ torque=0 ; ∑ M=0