1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
PilotLPTM [1.2K]
3 years ago
15

Two​ pulleys, one with radius r 1r1 and the other with radius r 2r2​, are connected by a belt. The pulley with radius r 1r1 rota

tes at omega 1ω1 revolutions per​ minute, whereas the pulley with radius r 2r2 rotates at omega 2ω2 revolutions per minute. Show that StartFraction r 1 Over r 2 EndFraction equals StartFraction omega 2 Over omega 1 EndFraction r1 r2
Mathematics
1 answer:
qwelly [4]3 years ago
3 0

Answer:

r1/r2 = 2ω2/ω1

Step-by-step explanation:

The velocity of each pulley is expressed as v = ωr where;

v is the linear velocity of the pulley

ω is the angular velocity of the pulley

r is the radius of the pulley.

For the two pulleys, the velocity I'd both pulleys are the same.

v1 = v2

v1 is the linear velocity of first pulley

v2 is the linear velocity of the second pulley.

v1 = ω1r1

v2 = 2ω2(r2)

r1 and r2 is the radius of pulley 1 and pulley 2 respectively.

Since v1 = v2

ω1r1 = 2ω2(r2)

Divide both sides by r2

ω1r1/r2 = 2ω2(r2)/r2

ω1r1/r2 = 2ω2

Divide both sides by ω1

ω1r1/r2/ω1= 2ω2/ω1

r1/r2 = 2ω2/ω1

You might be interested in
Random selection refers to
Andreyy89
Random selection refers to,

how subjects are picked from the population for inclusion in the study.

~~

I hope that helps you out!!

Any more questions, please feel free to ask me and I will gladly help you out!!

~Zoey
8 0
3 years ago
1. A 2002 poll reported that 61​% of people worried that they would be exposed to SARS.
Mama L [17]

Answer:

Part 1

a)ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{100}}=0.0956  

b) ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{363}}=0.0502

c) ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{1551}}=0.0243

Part 2

We can see that if we increase the sample size the margin of error decrease and that makes sense since n is on the denominator in the formula for the margin of error and if we increase the denominator the result needs to decrease.

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".  

The margin of error is the range of values below and above the sample statistic in a confidence interval.  

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".  

The population proportion have the following distribution

p \sim N(p,\sqrt{\frac{p(1-p)}{n}})

Part 1

For this case in order to find the margin of error we need to assume a confidence level fixed, let's assume 95% for example. The Margin of error is given by this formula:

ME= z_{\alpha/2}\sqrt{\frac{p(1-p)}{n}}

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by \alpha=1-0.95=0.05 and \alpha/2 =0.025. And the critical value would be given by:

z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96

The margin of error for the proportion interval is given by this formula:  

ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}    (a)  

And on this case we have that \hat p = 0.61 and we are interested in order to find the value of ME.

So we can replace for each case and see what we got:

a)ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{100}}=0.0956  

b) ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{363}}=0.0502

c) ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{1551}}=0.0243

Part 2

We can see that if we increase the sample size the margin of error decrease and that makes sense since n is on the denominator in the formula for the margin of error and if we increase the denominator the result needs to decrease.

7 0
4 years ago
cookies are sold singly or packages of 6 or 18. with this packaging, how many ways can you buy 36 cookies?. Help Please!
ki77a [65]
<span>Ok can't count properly, lets try again one package has 18,
how many ways?

18, 18
18, 6, 6, 6
18, 6, 6, ones
18, 6, ones
18, ones

Therefore, there are 5 ways to buy 36 cookies.

I hope my answer has come to your help. Thank you for posting your question here in Brainly.</span>
6 0
3 years ago
Read 2 more answers
4y³-2(2y-3)+y written in standard form​
Lady_Fox [76]

Mutiply the bracket by -2

(-2)(2y)=-4y

(-2)(-3)= 6

4y^3-4y+6+y

4y^3-4y+y+6 ( combine like terms)

4y^ 3-3y+6

Answer: 4y^ 3-3y+6

5 0
3 years ago
If f(x)=7x+4x and g(x) =1/2x what is the value of (f/g)(5)
Aliun [14]

Answer:

(f/g)(5) = 22

Step-by-step explanation:

All we need to do is plug in 5 for x in both f(x) and g(x) then divide the result of f(x) and g(x) to find our final answer.

Step 1: Plug in 5 for x

f(x) = 7(5) + 4(5) = 55

g(x) = 1/2(5) = 2.5

Step 2: Divide f(x) by g(x)

f(5)/g(5) = 55/2.5 = 22

And we have our final answer!

4 0
3 years ago
Other questions:
  • The line segment between the points (8,-7) and (4,5) is the diameter of the circle. Find the equation of this circle
    10·1 answer
  • If the fraction (352/x-10) is equivalent to -22, find the value of x.
    7·1 answer
  • What shape best describes the cross section cut at an angle to the base of a right rectangular prism? I already tried rectangle
    13·2 answers
  • Devon started the week with $50 in his checking account. On Monday he took $20 out of the
    10·2 answers
  • A right triangle has a height of 22 centimeters and a base of 11 centimeters What is the area of the triangle ?
    14·1 answer
  • I need an answer as soon as possible
    5·1 answer
  • Can someone help me with these 3 questions I'll mark u brainly :')​
    15·1 answer
  • Covent 13/10 to a mixed number
    13·1 answer
  • Which of the following is the rational exponent expression of 4 square root of f?
    11·1 answer
  • A system of equations is shown below. Solve for x.<br><br> y = x² - 6x + 4<br> y = x + 1
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!