# Physics

posted by .

To better understand the concept of static equilibrium a laboratory procedure asks the student to make a calculation before performing the experiment. The apparatus consists of a round level table in the center of which is a massless ring held in place with a pin. There are three strings tied to different spots on the ring. Each string passes parallel over the table and is individually strung over a frictionless pulley (there are three pulleys) where a mass is hung. The table is degree marked to indicate the position of each string. There is a mass of m1 = 0.151 kg located at è1 = 26.2° and a second mass of m2 = 0.215 kg located at è2 = 281°. Calculate the mass m3, and location (in degrees), è3, which will balance the system so the pin can be removed and the ring will remain stationary. The acceleration due to gravity is g = 9.81 m/s2.

• Physics -

F1=m*g = 0.151[26.2o]*9.8=1.480N[26.2o]

F2 = 0.215[281o]*9.8 = 2.107N[281o]

F3[Ao]

F = F1 + F2 + F3
F=1.480N[26.2o] + 2.107N[281] + F3[Ao]

X = 1.480*cos26.2+2.107*cos281+F3*cosA=0
X = 1.328 + 0.4020 + F3*cosA = 0
F3*cosA = -1.73
cosA = -1.73/F3.

Y = 1.480*sin26.2+2.107*sin281+F3*sinA=0
Y = 0.6534 - 2.068 + F3*sinA = 0
F3*sinA = 1.415
sinA = 1.415/F3

sinA/cosA = (1.415/F3)/(-1.73/F3) =
1.415/-1.73 = -0.81792 = TanA
A = -39.3o = 320.7o, CCW.

F3*sinA = 1.415
F3 = 1.415/sinA = 1.415/sin320.7=-2.23 N[320.7o]

m3*g = -2.23
m3=-2.23/g = -2.23/-9.8=0.228 kg[320.7o]

## Similar Questions

1. ### AED

Choose a grade level and a scientific concept appropriate for that level. • Plan a science experiment to explore this concept. In your paper, address the following points: o List the equipment and materials to be included in the …
2. ### Physics

A student wants to run an experiment to determine how the distribution of mass (location of mass) affects an object`s rotational velocity. For this experiment the student picks 3 rings. One is a wood ring (like a hula-hoop) with all …
3. ### Physics

Hello I have an assignment to do about the force table. I'm not sure about my answers, hope someone could check it for me if I answered correctly. 1.What kind of forces do you use on the force table?
4. ### physics

the three weights are hanging in static equilibrium. The two weights left and right of center have a mass of 100 Kg. The weight in the center has a mass of 100 Kg. Treat the strings as massless and the pulleys as frictionless. If the …
5. ### physics

the system is in static equilibrium. The coefficient of static friction between the block and the table's surface is = 1/3. The mass of the block that is hanging down is n1 Kg. The tangent of the angle shown in the figure is tan theta …
6. ### Physics

Two point charges, +Q and -Q of mass m, are placed on the ends of a massless rod of length L, which is fixed to a table by a pin through its center. If the apparatus is then subjected to a uniform electric field E parallel to the table …
7. ### Physics

Two point charges, +Q and -Q of mass m, are placed on the ends of a massless rod of length L, which is fixed to a table by a pin through its center. If the apparatus is then subjected to a uniform electric field E parallel to the table …
8. ### physics

Two students, Jahna, and Raul, re performing Experiment 1. To simplify their calculations, each will apply their force perpendicular to the arm of the apparatus. Jahna attaches her spring scale 15cm from the pivot and pulls with a …
9. ### Physics

In a Physics laboratory class, an object of mass 2.1 kg, attached by massless strings to two hanging masses, m1= 1.0 kg and m2= 4.0 kg, is free to slide on the surface of the table. the coefficient of kinetic friction between m2 and …
10. ### chemistry

A Biology student wants to know if Mountain Dew will make plants grow faster than water. As a Chemistry student, you have agreed to assist in the planning of the experiment to make sure the student designs a valid experiment. 1) What …

More Similar Questions