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

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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.

how environment affect demand and supply of commodity ?
Wht at the criteria for market ?
Amos
what is difference between monitory policy and fiscal policy?
monetary policy is a policy thrust by National Govt(CBN) to influence government spending, purchase &taxes
Frank
necessity of economics
I will say want,choice,opportunity cost,scarcity,scale of preference
Alao
what is monopoly market.How price output are determined under monopoly market
bisham
b) Monopoly market is an impecfect market where s single firm having the innovation to produce a particular commodity.Prices are determined through output since there are no other competitive.
Frank
Monopoly market:firm has market power & does not respond to market price
Frank
Explain the process of price determination under perfect competition market with suitable diagram
Price determination under perfect competition via this process :firms have no market power to influence price rather firms respond to market price.
Frank
price is different from demand- demand is amount of commodity
demand is amount /quantity of commodity a potential buyer is willing to buy at a given price at market
Frank
demand is a desire of customer on commodity with the ability to pay it and willing to buy it at given price of commodity
Harika
demand is price of what
show that shortrun average cost
what is economics
what is money
Mbah
what is money
Mbah
Difine macro economics
agaba
money is a medium of exchange between goods and services,maybe inform of currency.
Wesonga
Economics is study of how human beings strive to satisfy numerous wants using limited available resources.
Wesonga
how do you find the maximum number of workers the firms should employ order to produce where there are increasing returns
Jane
what are implications of computing national income?.
agaba
pl
MUDASIRU
what is the formulae for calculating national income
MUDASIRU
it calculated by value added method
Praveen
classify the production units like agriculture, banking, transport etc
Praveen
money is anything that is generally acceptetable for human
Ogbaji
Estimate the net value added(NVA) at fixed cost by each industrial structure
Praveen
definition of unemployment
what are the causes of unemployment?
The main causes of unemployment are listed below. 1. Frictional unemployment 2. Cyclical unemployment 3. Structural unemployment
assani
We can also categorize the causes on a broader sense as: 1. Political and 2. Social cause As unemployeement root causes are embaded in this two.
Yonathan
would opportunity cost exist if there was no scarcity?
assani
yes just because the opportunity cost arose when there is Alternative to choose among the alternatives.
I am thinking that, if our resources were unlimited, then there wouldn't be any need to forgo some wants. Hence the inexistence if opportunity cost
assani
Politics
Job
politics has done what?
assani
consider time assani
Mary
I'm Emmanuel,...I taught the main cause is the change in gov't.
Emmanuel
...Lack of capital to set up a firm respectively
Emmanuel
🙈
Emmanuel
I would like to bring in Educational levels can also be the cause the cause of the problem respectively
Emmanuel
I think the main causes of unemployment is lack of INFRASTRUCTURAL DEVELOPMENT OVER POPULATION OVER DEPENDENT ON GOVERNMENT LACK OF SELF EMPOWERMENT...
ananti
lack of skills among the new generation is the serious issue.
Vishal
Where I come from , I don't see why education or personal aspects seem to do with unimployment, technically the motivation and eigerness in all works of live is there , dispite the cultural influence and physical bearriors;the thing we lacking is Government Support and open market ethics.
Joe
sorry about that-(repation). We have a over powering ethical political system that's displacing the marketing asspects of economy and causing large scale unemployment right across the board...
Joe
can someone Explain Expansionary Monetary Policy and Contractionary Monetary Policy Using one of the instrument of Monetary Policy? Please am kinda lost here?. ta
using a graph show the case of substitute and compliment goods
can anyone give me a simple explanation to Five Sector Macroeconomics?
Emmanuel
Can someone please define what economics is
economics simply is a social science subject that study human behavior.
dajan
economics is a social science which studies human behaviour as a relationship between ends and scarce means that has alternative uses
Alao
Can someone please tell me how to calculate GDP
Emmanuel
emmanual kapal to calculate GDP (Gross Domestic Product) has three method in calculating it (1)income approach (2) expenditure approach (3) value added method
Alao
thanks Alae
Emmanuel
u are welcome
Alao
in basic terms economics is revered to as battery system, it date back to when Men sees the need to exchange sapless goods and produce to gain , either wealth , basic necessities or to establish trading ties for personal benefit or social asspects in terms of coexistence and continuity, future .
Joe
what is the law of demand
keep other thing constant, when the price increases demand decrease when the price decreases demand increases of the commodity.
sj
all things being equal,quantity demanded decrease as price increase and increase as price decrease
Seth
there's practial joke to it ..." the higher the demand ; scarcity, increase in production and drop in quality"... quite the controversy - for example China vs Europe, United States and we are all boxed up in between somewhere...
Joe
Other thing remain constant the low price of commodity the high quantity of commodity and vice versa is true
Baraka
Explain Effective demand
What is effective demand
Anita
like Modi is in demand...best example of effective demand
Pranav
Don't get you
Anita
Anita you mean you don't get me or who?
Onyeking
level of demand that represents a real intention to purchase by people with the means to pay
Pranav
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