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Mark four points with pins

Assume that the lower left corner of the square is the origin with coordinates of x=0 and y=0. Place pins at the following coordinate positions:

  • A. x=1, y=1
  • B.x=1, y=2
  • C. x=3, y=2
  • D. x=2, y=1

Draw vectors

Now use rubber bands or pipe cleaners to draw the following force vectors originating at the locations of the pins. (Positive angles are measured counter-clockwise relative to the positive xaxis.)

  • A. 5 units magnitude at 180 degrees
  • B. 2.8 units magnitude at 45 degrees
  • C. 3 units magnitude at 0 degrees
  • D. 2 units magnitude at -90 or +270 degrees

Tactile graphics

The svg file that is required to create tactile graphics for this exercise is named Phy1110a1.svg. You should have downloaded that file earlier. This file contains a vector diagram that represents the instructions given above .

Figure 1 shows the mirror image that is contained in that file for the benefit of your assistant who will create the tactile graphicfor this exercise.

Figure 1 . Mirror image from the file named Phy1110a1.svg.
Missing image

Figure 2 shows a non-mirror-image version of the same image.

Figure 2 . Non-mirror-image version of the image from the file named Phy1110a1.svg.
Missing image

Figure 3 shows the key-value pairs that go with the image in the file named Phy1110a1.svg.

Figure 3 . Key-value pairs for the image in the file named Phy1110a1.svg.
m: Equilibrium for a body with an arbitrary shape n: Bo: C p: Dq: A r: File: Phy1110a1.svgs: The sum of the torques about point D is - 8.936.

Compute the vector sum of the forces

Begin by computing the horizontal and vertical components of the force at B. As you know by now, the horizontal component is equal to the magnitude ofthe vector (2.8) multiplied by the cosine of 45 degrees and the vertical component is equal to the magnitude of the vector multiplied by the sine of 45degrees. Both the sine and the cosine of 45 degrees is 0.707, so the horizontal and vertical components are both equal to 2. (Obviously, I planned it that way.)

The horizontal and vertical components

The remaining vectors are either horizontal or vertical so no trigonometry is required to compute their components.

The horizontal components of all the vectors consist of:

  • A. 5 units at 180 degrees = -5
  • Bx. 2 units at 0 degrees = +2
  • C. 3 units at 0 degrees = +3

The sum of the horizontal components is 0.

The vertical components of all the vectors consist of:

  • By. 2 units at 90 degrees = +2
  • D. 2 units at -90 or +270 degrees = -2

The sum of the vertical components is also 0. Therefore, the system exhibits the first condition of equilibrium.

Compute the moment or torque

The second condition for equilibrium states that the sum of all torques acting on the body measured about any axis must be zero.

You can often reduce the complexity of the computation for computing torque by judicious selection of the point about which the torque will be computed.

Compute the torque about point D

In this case, we can simplify the arithmetic by choosing an axis that goes through the point at D.

If you examine your graph, you will see that the line of action for forces A and D both go through the point at D. Therefore, neither of those forces createsa moment about point D so we can exclude them from our computation.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Accessible physics concepts for blind students. OpenStax CNX. Oct 02, 2015 Download for free at https://legacy.cnx.org/content/col11294/1.36
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