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Group No. 3 Section: 2A PH13 Cope, Pamela Marie Date performed:
January 16, 201214 Corteza, Zigmund Bryan Date submitted: February
06, 201215 Cua, Jerry16 Del Prado, Jeprel
17 Florano, Solmuell18 Florentino, Mary Roxine
EXPERIMENT NO. 3EQUILIBRANT & RESULTANT FORCES
ABSTRACT:
The resultant force is defined as the vector sum of forces,
while the equilibrant force is defined asthe force that balances
the resultant force to produce equilibrium. There are two ways of
gettingthe resultant force. The first, the experimental method, is
done by getting the negative vector ofthe equilibrant force in
polar form (r,sp), which is done by copying the magnitude
(r),thenadding or subtracting 180 to the direction of the force
(sp). The second, the component method,is done by resolving the
vectors to be added into its rectangular form , then adding
thesecomponents together before re-converting the acquired sum into
polar form. In this experimentthree forces acting on a washer were
balanced on a force table. Experimental data on theequilibrant
forces was written down based on the readings on the weights for
the magnitude andthe force table for the direction. Then the
theoretical resultant forces were computed using thecomponent
method to check if the answers will be almost, if not the same, as
the experimentaldata on the equilibrant forces gathered
GUIDE QUESTIONS:
1. Differentiate the resultant and equilibrant of two
forces.
Resultant Force is the sum of all forces acting on a system in a
given time whileEquilibrant is the opposite but equal force with
respect to the Resultant Force. TheEquilibrant Force has a
magnitude equal to that of the Resultant Force and a
directionopposite the direction of the Resultant.
2. If three concurrent forces are in equilibrium, what is the
relation between any one of the
three forces and the resultant of the other two forces?
Any one of the three forces is the negative vector of the
resultant of the other two forces,meaning they possess the same
magnitude but are opposite in direction and vice-versa.
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3. If two forces with the same magnitude were exactly in
opposite direction, what is themagnitude and direction of their
resultant? What is the magnitude and direction of their
equilibrium?
The resultant is zero, i.e., the system does not move and is in
equilibrium already.
4. Use the component method to find the magnitude and direction
of the resultant of theconcurrent forces given below:
A 2000N at 0oB 1500N at 60o C 1000 N at 150o D 3800N at 225o
x = r cos y = sin FA (2000 N, 0o) 2000 0FB (1500 N, 60o) 750
1300FC (1000 N, 150o) -900 500FD (3800 N, 225o) -2700 -2700
FX= -850 N FY= -900 N
(-x,-y) therefore (FX,FY) is in Quadrant III.
|Magnitude| = (x2 + y2)= [(-850 N)2 + (-900 N)2]= (720000 N2+
810000 N2)= 1530000 N2 = 1240 N
Direction: tan = y / x= (-900 N) / (-850 N)= tan-11 = 45=180o +
45o = 225o
Resultant Force: (1240 N, 225o)
