# 0.11 Phy1080: motion -- variable velocity and acceleration  (Page 6/19)

 Page 6 / 19

Analysis of the output

You should be able to tell that your curve begins at a height of 6 feet and increases on a point-by-point basis out to about 3 seconds. The maximumvalue should occur around 3 seconds and the plot should go to zero between 6.25 seconds and 6.5 seconds.

Not a trip to outer space

As you are probably aware, shooting an arrow upward does not cause the arrow to go into outer space, unless the arrow is self-propelled and manages to reach avelocity commonly known as the "escape velocity."

Instead, for any practical value of initial velocity (neglecting air resistance), gravitationalattraction will eventually cause the arrow to slow down, reverse course, and fall back to earth with continually increasing velocity until it strikes theearth and stops. That is the message conveyed by the plot on your graph board.

The maximum height

At about 3 seconds and a height of about 161 feet, the kinetic energy provided by the initial velocity will have been dissipated by the gravitationalattraction of the earth. At that point, the arrow won't go any higher. Instead, it will start falling back toward the earth. Somewhere around 6.25 seconds, itwill strike the earth.

The shape of the curve

The shape of this curve is controlled by only two factors: the initial velocity of the arrow and the gravitational attraction of the earth. The archerhas some degree of control over the initial velocity, but has no control over the gravitational attraction of the earth.

In theory, in the absence of an atmosphere, if the arrow is shot straight up, the arrow should land in the same place from which it was shot. In practice in the real world, wind and other factors wouldprobably prevent that from happening.

Variable velocity

We learned in an earlier module that if velocity is uniform, the displacement should be the same during each successive equal interval oftime. However, we can see from Figure 4 that is not true in this case. For example, Figure 5 shows the displacement versus time for the first five time intervals and we can see that it is anything but uniform.

Figure 5 . Displacement versus time for first five time intervals.
Interval Displacement 1 242 22 3 204 17.9 5 15.9

Successively decreasing or increasing displacement

Referring back to Figure 4 (along with Figure 5 ), we see that the displacement during the first 0.25 second time interval was 24 feet, but the displacementbetween 2.75 seconds and 3.0 seconds was only 1.9 feet, Furthermore, the displacement was -0.2 feet during the interval between 3 seconds and 3.25 second indicating that the arrow had begun falling back to the earth.

From that point until contact with the ground, the displacement increased during each 0.25 second interval.

In this case, the velocity clearly wasn't uniform. Instead it was variable.

Measuring variable velocity in the real world

Measuring variable velocity in the real world can be difficult. What you need to do is to measure the displacement of an object in as short a time interval aspossible and then divide the displacement by the value of the time interval. If you can do this at enough points in time, you can construct curves thatrepresent the variable velocity to which the object is being subjected.

can someone help me with some logarithmic and exponential equations.
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
Commplementary angles
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
a perfect square v²+2v+_
kkk nice
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
rolling four fair dice and getting an even number an all four dice
Kristine 2*2*2=8
Differences Between Laspeyres and Paasche Indices
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
is it 3×y ?
J, combine like terms 7x-4y
im not good at math so would this help me
yes
Asali
I'm not good at math so would you help me
Samantha
what is the problem that i will help you to self with?
Asali
how do you translate this in Algebraic Expressions
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
what's the easiest and fastest way to the synthesize AgNP?
China
Cied
types of nano material
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
what is nanomaterials​ and their applications of sensors.
what is nano technology
what is system testing?
preparation of nanomaterial
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
what is system testing
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
can nanotechnology change the direction of the face of the world
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
how did you get the value of 2000N.What calculations are needed to arrive at it
Privacy Information Security Software Version 1.1a
Good
Got questions? Join the online conversation and get instant answers!