coverage of the 1st long test
DESCRIPTION
Coverage of the 1st Long test. Newton’s Laws of Motion graphing vectors calculating components of vectors (horizontal and vertical components) getting the resultant vector using the component method free- body diagram Static equilibrium calculating forces involved in a given system. 37°. - PowerPoint PPT PresentationTRANSCRIPT
Coverage of the 1st Long test
• Newton’s Laws of Motion• graphing vectors• calculating components of vectors
(horizontal and vertical components)• getting the resultant vector using the component
method• free- body diagram• Static equilibrium• calculating forces involved in a given system
37°
37°
37°
Static Equilibrium
Condition 1
Σ Fx = 0
Σ Fy = 0
Σ Fz = 0
Condition 2
The sum of the
torque, ז, is zero.
Center of Gravity
• the point where the force of gravity is concentrated
When the center of
gravity falls within the
base of the object, then
the object is stable.
Static
60° 60°
Object in free-fall
Fgravity
Objects falling at constant velocity (terminal velocity)
F air friction
F gravity
Object sliding at constant velocity(the surface is frictionless)
F normal
F gravity
Object sliding without friction
F gravity
F normal
Is the box accelerating?
mass of the block = 10kg
10N 5N
F applied Ff F normal
10 N
5N
F gravity
Is the box accelerating? mass of the block = 10kg
Σ Fy = Fnormal + Fgravity= 0
Fgravity = Weight = mass X acceleration = 10 kg X - 9.8 m/s2
= - 98 kgm/s2
= - 98 N
Σ Fy = Fnormal + ( -98 N) = 0 Fnormal = 98 N
F normal
F applied = 10 N
Ff = 5N
F gravity
Is the box accelerating? mass of the block = 10kg
Σ F x = Fapplied + Ff
Σ Fx = 10 N + (-5N) = 5N
Fnet = 5N = massX acceleration 5N = 10 kg X a a = 0.5 m/s2
F normal
F applied = 10 N
Ff = 5N
F gravity
Note: There is friction between the load and the incline.
• http://www.google.com.ph/imgres
Draw the FBD of the box
Draw the FBD of the knot (include the angle).
A B
C
Summary
• The object is in static equilibrium if it is not moving and not rotating.
• A free-body diagram can be drawn to evaluate the effect of forces on the object.
• There is always a force of gravity (also known as weight) which is equal to the product of the mass and acceleration due to gravity.
• There is a normal force perpendicular to the surface that supports and balances the object vertically.