A stone is dropped into a lake, creating a circular ripple that travels outward at a speed of 50 cm/s. Find the rate at which the area within the circle is increasing after each of the following.
(a) after 1 s
(b) after 3 s
(c) after 7 s

Answers

Answer 1

Answer:

1.) 15,708cm^2/s

2) 47,124cm^2/s

3.) 109,956cm^2/s

Step-by-step explanation:

Given the following:

50cm/s is the radius of the ripple per second , that is, radius(r) of ripple after t seconds = speed * time(t)

Speed = 50cm/s

r = 50t

.area of a circle(A) = πr^2

Rate of change of area with radius :

dA/dt = π2r . dr/dt

Speed of ripple created = 50cm/s; this is the rate at which the radius changes with time (dr/dt)

dr/dt = 50cm/s

Rate at which area is increasing with time:

dA/dt = π2r . dr/dt

dA/dt = π2(50t).50

dA/dt = 5000πt

After 1 second:

dA/dt = 5000π(1)

= 15,707.963cm^2/s

After 3 second:

dA/dt = 5000π(3)

= 47,123.889cm^2/s

After 7 second:

dA/dt = 5000π(7)

= 109,955.74cm^2/s


Related Questions

How to solve the equation 4×3−15÷3×2+1

Answers

Answer:

3

Step-by-step explanation:

We use Order of Operations BPEMDAS.

Step 1: Multiply

12 - 15/3(2) + 1

Step 2: Divide

12 - 5(2) + 1

Step 3: Multiply

12 - 10 + 1

Step 4: Subtract

2 + 1

Step 5: Add

3

Answer: 3

Step-by-step explanation:

PEMDAS

P: No parenthesis

E: No exponents

M and D: 4x3 = 12(12-15÷3×2+1), 15÷3 = 5(12-5×2+1), 5*2 = 10(12-10+1)

A and S: 12-10 = 2(2+1), 2+1=3(3)

let f(x)=2x^2 and g(x)=x^-2 find f(g(x))

Answers

Answer:

2x^-4  or 2/x^4.

Step-by-step explanation:

We replace the x in f(x) by g(x).

f(g(x)) =  2 (x^-2)^2

= 2 x^(-2*2)

= 2x^-4

= 2/x^4.

Find the measure of each angle: Complementary angles with measures (5x)° and (4x−18)°

Answers

Answer:

60° and 30°

Step-by-step explanation:

Since they are complementary, the 2 equations add up to 90°

5x + 4x - 18 = 90

9x - 18 = 90

9x = 108

x = 12

Simply plug in x to find our angles:

5(12) = 60°

4(12) - 18 = 48 - 18 = 30°

Answer:

5x = 60°, 4x - 18 = 30°

Step-by-step explanation:

Sum of complementary angles is 90°.

5x + 4x - 18 = 90

9x = 90+18

9x = 108

x = 12

5x = 5* 12= 60°

4x - 18 = 4*12 - 18 = 30°

The probability that Stu buys a sandwich is 0.5.
The probability that Stu gets the bus is 0.7.
Assuming the events are independent, what is the probability that Stu buys a sandwich and gets the bus?

Answers

Answer:

probability that Stu buys a sandwich and gets the bus = 0.35

Step-by-step explanation:

Probability of success of two independent events is the product of the respective probabilities, i.e. the multiplication rule.

P(Sandwich) = P(S) = 0.5

P(Bus) = P(B) = 0.7

Assuming the events are independent,

probability that Stu buys a sandwich and gets the bus

= P(SB) = P(S)*P(B) = 0.5*0.7 = 0.35

Answer: 0.35

Step-by-step explanation:

First there is a 50% chance, or a 0.5 chance that Stu gets a sandwich.  Then, ignoring the other .5, there is a .7 chance that he makes the bus.  Thus, 1/2 of .7 is 0.35.

Hope it helps <3

Explain the steps you would take to find the quotient of 1/3 divided 4/3

Answers

Answer:

1/4

Explanation:

1/3 is the dividend while 4/3 is the divisor.

The quotient is the resulting number after the division is made.

1/3 divided by 4/3

Is the same as

1/3 x 3/4

This results in 3/12 which when simplified is 1/4

Answer: 1/4

Step-by-step explanation: Here, we have 1/3 ÷ 4/3.

Dividing by a fraction is the same

as multiplying by its reciprocal.

In other words, we can change the division sign

to multiplication and flip the second fraction.

So here, 1/3 ÷ 4/3 can be rewritten as 1/3 × 3/4.

Now we're simply multiplying fractions.

Before multiplying however, always try to cross-cancel.

Notice that we can cross-cancel 3 and 3 to 1 and 1.

So we now have 1/1 × 1/4.

Multiplying across the numerators

and denominators, we have 1/4.

TEN POINTS !!!!1 . Type the correct answer in the box. Simplify this expression:

Answers

Answer:

1

Step-by-step explanation:

Add the exponents of the as inside the parenthesis.

8+6 =14

Power to a power = multiplication of exponents.

14 times 1/7 = 2

[tex]\frac{a^2}{a^2}[/tex] When you divide, subtract exponents.

2-2 = 0

Any number to the zeroth = 1

The answer is 1.

In the figure, triangle ABC is similar to triangle APQ. Therefore, the value of x is , and the value of y is

Answers

Answer:

the same

Step-by-step explanation:

Answer:

Step-by-step explanation:

x = 70 degrees.

All triangles have 180 degrees.

So ABC has 180 degrees.

70 + 50 + ACB = 180 Combine like terms

120 + ACB = 180 Subtract 120 from both sides

ACB = 180 - 120

ACB = 60

y = ACB

y = 60 degrees

Jordan lives 6 kilometers due south of his parents' house and 4 kilometers west of his grandparents' house. On his birthday, Jordan drove from his house to his parents' house. From there, he drove in a straight line to his grandparents' house and then back home. How far did Jordan drive on his birthday? If necessary, round to the nearest tenth.

Answers

Answer:

Step-by-step explanation:

The direction of movement of Jordan on his birthday forms a right angle triangle. His movement from his house to his parents due south represents the opposite side of the right angle triangle. His movement due west represents the adjacent side and the movement back home along the straight line, d represents the hypotenuse. To determine d, we would apply the Pythagorean theorem. Thus

d² = 6² + 4² = 52

d = √52 = 7.2 km

The total distance that he drove on his birthday is

6 + 4 + 7.2 = 17.2 km

Is Triangle ABC cong Triangle DEF? If so name the postulate that applies

Answers

Answer:

D. Congruent - SAS

Step-by-step explanation:

Two sides and the included angle of a triangle are congruent to the corresponding parts of another triangle.

The triangles are congruent by SAS.

How can we interpret the independent or conditional probability of two events?

Answers

Hello!

A conditional probability can always be computed using the formula in the definition. Sometimes it can be computed by discarding part of the sample space. Two events A and B are independent if the probability P(A∩B) of their intersection A ∩ B is equal to the product P(A)·P(B) of their individual probabilities.

Hope this helps.

Pleaaaaase help!!!!​

Answers

Answer:

see below

Step-by-step explanation:

sqrt(20)

sqrt(4*5)

We know that sqrt(ab) = sqrt(a) sqrt(b)

sqrt(4) sqrt(5)

2 sqrt(5)

Answer:

We can factor down 20 with it's greatest prime GCF, which is 5. We get a 4. When we factor that down the same way, we get 2. If we repeat that process, we get 5, 2, and 2, which turns into [tex]2\sqrt{5}[/tex].

Quadrilateral rust has a vertex (2,4). What are the coordinates of r' after a dilation of scale factor 3, centered at the origin, followed by translation (x,y) to (x+4,y)

Answers

Answer:

The coordinates of r' are x = 10 and y = 12.

Step-by-step explanation:

The vertex experiments two operations: Dilation and translation, whose definitions are presented herein:

Dilation with respect to origin

[tex](x',y') = (0,0) + 3\cdot (x,y)[/tex], [tex]\forall \,x,y \in \mathbb{R}[/tex]

Translation

[tex](x',y') =(x+4,y)[/tex], [tex]\forall\,x,y\in \mathbb{R}[/tex]

If [tex]x = 2[/tex] and [tex]y = 4[/tex], then:

1) [tex](2,4)[/tex] Given.

2) [tex](0,0) + 3\cdot (2,4)[/tex] Dilation with respect to origin.

3) [tex](6,12)[/tex] Vectorial sum and scalar multiplication.

4) [tex](6+4,12)[/tex] Translation.

5) [tex](10,12)[/tex] Vectorial sum. Result.

The coordinates of r' are x = 10 and y = 12.

Answer:

10,12 is the answer

Step-by-step explanation:

I just did it on a p e x

Question 1) While traveling to Europe, Phelan exchanged 250 US dollars for euros. He spent 150 euros on his trip. After returning to the United States he converts his money back to US dollars. How much of the original 250 US dollars does Phelan now have? Round to the nearest cent. 1 European euro = 1.3687 US dollars Question 2) To fit between two windows, the width of a bookshelf must be no greater than Six and one half feet. Mrs. Aguilar purchases a bookshelf that is 77 inches wide. Which statement describes the relationship between the width of the bookshelf and the distance between the windows? Question 3) Alina is able to swim at a rate of about 2.5 miles per hour. Talia is able to swim at a rate of 1.8 meters per second. Which statement comparing the two swimmers is accurate? 1 mile 1,609 meters.

Answers

Pharrell Williams produced most of Justin Timberlakes critically acclaimed debut solo album Justified.

If f(x) = x - 3, which of the following is the inverse of f(x)?
O A. f-'(x) = x-3
O B. f-'(X) = x + 3
O c. f-'(X= 3x
O D. f-'(x) = 3 - x

Answers

Answer:

B. f^-1(x) = x+3

Step-by-step explanation:

Given the function f(x) = x-3, to get its inverse, the following steps mist be followed.

First we will make y = f(x)

y = x-3

Then we will make x the subject of the formula to have:

y+3 = x-3+3

y+3 = x

x = y+3

Finally, we will replace back y with x to have:

y = x + 3

f^-1(x) = x+3

This gives the inverse of the function.

please hellppp please hellpp​

Answers

Answer:

- 3 and 5

Step-by-step explanation:

The equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y- intercept )

y = - 3x + 5 ← is in slope- intercept form

with slope m = - 3 and y- intercept c = 5

Answer:

the slope (gradient) is -3, and the y-intercept is +5

Step-by-step explanation:

A line in the slope-intercept form

   y = mx + b

has a slope of m and a y-intercept of b

Therefore for the line

  y=-3x + 5

the slope (gradient) is -3, and the y-intercept is +5

1) Which of the following is a surd ? a) 64 b) 6 root 64 c) 4 root 64 d) 3 root 64

Answers

Answer:

  [tex]\text{c) }\sqrt[4]{64}=2\sqrt[4]{4}[/tex]

Step-by-step explanation:

[tex]\text{a) }64\qquad\text{an integer; not a surd}\\\\\text{b) }\sqrt[6]{64}=2\qquad\text{an integer; not a surd}\\\\\text{c) }\sqrt[4]{64}=2\sqrt[4]{4}\qquad\textbf{a surd}\\\\\text{d) }\sqrt[3]{64}=4\qquad\text{an integer; not a surd}[/tex]

Simplify: ( ++)2 + ( −+)2 + ( +−)2

Answers

Answer:

[tex]-2[/tex]

Step-by-step explanation:

[tex]( ++)2 + ( -+)2 + ( +-)2[/tex]

[tex]++ = +[/tex]

[tex]-+ = -[/tex]

[tex]+- = -[/tex]

[tex]( +)2 + ( -)2 + ( -)2[/tex]

[tex]2-2-2[/tex]

[tex]=-2[/tex]

Figure 6.21
From knowledge of the sum of the angles
at a point.
b By calculating the sizes of the angles of a
regular octagon using the (n - 2) × 180°
formula​

Answers

Answer:

L

Step-by-step explanation:

360 hhjnjjuffdsaadt

Simplify the following expression: (1 point) 2x − 2y + 5z − 2x − y + 3z

Answers

Answer: -3y + 8z

Step-by-step explanation:

2x -2x = 0

-2y + - y= -3y

5z + 3z= 8z

-3y + 8z

The expression 2x − 2y + 5z − 2x − y + 3z is simplified as − 3y + 8z.

What is simplification?

Making anything easier to accomplish or comprehend, as well as making it less difficult, is the definition of simplification.

PEMDAS rule means for the Parenthesis, Exponent, Multiplication, Division, Addition, and Subtraction. This rule is used to solve the equation in a proper and correct manner.

The expression is given below.

⇒ 2x − 2y + 5z − 2x − y + 3z

Simplify the expression, then we have

⇒ 2x − 2y + 5z − 2x − y + 3z

⇒ 2x − 2x − 2y − y + 5z + 3z

⇒ 0 − 3y + 8z

⇒ − 3y + 8z

The expression 2x − 2y + 5z − 2x − y + 3z is simplified as − 3y + 8z.

More about the simplification link is given below.

https://brainly.com/question/12616840

#SPJ2

a man bought second hand bicycle for rs 1120 and spend rs160 to repair it. he sold it for rs1344, find his profit or loss percent ​

Answers

Answer:

5 %

Solution,

Total Cost price (CP) = Rs 1120 + Rs 160

= Rs 1280

Selling Price (SP) = Rs 1344

Here,

SP > CP , so he made profit.

Amount of profit = SP - CP

= Rs 1344 - Rs 1280

= Rs 64

Now, finding the profit percent,

Profit %=[tex] \frac{profit \: }{cp} \times 100 \: percent[/tex]

[tex] \frac{64}{1280} \times 100 \: percent[/tex]

[tex]5 \: percent[/tex]

Profit percent = 5%

Hope this helps...

Good luck on your assignment...

Write a polynomial f(x)that satisfies the given conditions,
Polynomial of lowest degree with zeros of - 4 (multiplety 1), 3 (multiplicly 3), and with f(0)= 216,

Answers

Answer:

[tex]\boxed{\sf \ \ \ -2(x+4)(x-3)^3 \ \ \ }[/tex]

Step-by-step explanation:

Hello,

let's note k a real, we can write the polynomial as

[tex]k(x-(-4))^1(x-3)^3=k(x+4)(x-3)^3[/tex]

and we know that f(0)=216 so

[tex]216=k(0+4)(0-3)^3=k*4*(-1)^3*3^3=-27*4*k=-108k\\\\<=> k=-\dfrac{216}{108}=-2[/tex]

So the solution is

[tex]-2(x+4)(x-3)^3[/tex]

hope this helps

A bag contains orange, purple, and blue marbles. If a marble is selected at random from the bag, the probability it is orange is 0.2, the probability it is purple is 0.3, and the probability it is blue is 0.5. Which colour marble is most likely to be selected? Explain.

Answers

Answer:

blue marble

Step-by-step explanation:

Probability is how likely something is to happen. Between the three colors, blue has the greatest probability, meaning it will most likely be selected.

0.5 > 0.2

0.5 > 0.3  

help me quickly please!!! what is the area of the composite figure if line AB is congruent to line BC which is congruent to line CD which is congruent to line DA which is congruent to DN?
(2pi+28)mm^2
(2pi+32)mm^2
(2pi+40)mm^2
(2pi+48)mm^2

Answers

Answer: Choice C. 2pi+40 square mm

======================================================

Work Shown:

Segments AB, BC, CD, DA, and DN are all the same length (4 units)

The semicircle has area of

A = (1/2)*pi*(radius)^2

A = 0.5*pi*2^2

A = 2pi

The square has area of

B = (side length)^2

B = 4^2

B = 16

The trapezoid has area of

C = (height)*(base1+base2)/2

C = (DN)*(CD+MK)/2

C = (4)*(4+8)/2

C = 24

Add up the results of A, B and C to get the total area

A+B+C = 2pi+16+24 = 2pi+40

The total area is 2pi+40 square mm

The area of the figure will be 2π + 40 mm². Then the correct option is C.

What is the area?

The area of a two - dimensional figure is the area that its perimeter encloses. The quantity of unit squares that occupy a closed figure's surface is its region.

The figure is made by semicircle, square, and trapezium. Then the area is given as,

A = Area of a semicircle + Area of square + Area of trapezium

A = (π / 2) x r² + (AB)² + 1/2 x (CD + MK) x DN

A = (π / 2) x 2² + (2 x 2)² + 1/2 x (4 + 8) x 4

A = 2π + 16 + 24

A = 2π + 40 mm²

The area of the figure will be 2π + 40 mm². Then the correct option is C.

More about the area link is given below.

https://brainly.com/question/27683633

#SPJ7

In a geometric series, the first term is 108 and the common ratio is \frac{2}{3}. Find the sum of the first 8 terms.

Answers

Answer:

311.36

Step-by-step explanation:

For  a geometric series sum of first n terms is [tex]a(1-r^n)/(1-r)[/tex]

if r is less than 1.

where a is the first term and r is the common ratio.

____________________________\

given

a = 108

r = [tex]\frac{2}{3}.[/tex]

n = 8

thus , sum of n term is

[tex]a(1-r^n)/(1-r)\\=>108(1-(2/3)^8)/(1-2/3)\\=> 108 (1 - 256/6561)/1/3\\=> 108(6561-256)/ 6561/1/3\\=> 108(6305)/2187\\=>311.36[/tex]

Thus sum of first 8 terms is 311.36

f(x) = 3x + 2
What is f(5)?

Answers

Answer:

17

Step-by-step explanation:

3(5) + 2 = 15 + 2

= 17

Therefore x= 17

Answer:

[tex]\huge\boxed{f(5)=17}[/tex]

Step-by-step explanation:

[tex]f(x)=3x+2\\\\f(5)=?\\\\\text{substitute}\ x=5\ \text{to}\ f(x):\\\\f(5)=3(5)+2=15+2=17[/tex]

The two cones are similar. (a) Write down the value of l. (b) When full, the larger cone contains 172 cm3 of water. How much water does the smaller cone contain when it isfull?

Answers

Answer/Step-by-step explanation:

a. Since both cones, as shown in the figure attached below, are similar, 11/8 = l/4

Cross multiply to find l

4*11 = 8*l

44 = 8l

l = 44/8

l = 5.5cm

b. Given the slant height and diameter of cone, volume of cone can be calculated using the formula ⅓πr²*√(l² - r²)

Where, r = diameter ÷ 2 = 4/2 = 2cm

l = 5.5cm

Volume of smaller cone = ⅓*3.142*2²*√(5.5² - 2²)

= ⅓*3.142*4*√30.25 - 4)

= ⅓*12.568*√26.25

= ⅓*12.568*5.124

= 64.40/3

Volume of small cone ≈ 21.5 cm³

Find the y-intercept of the parabola y = x2 – 8.
Simplify your answer and write it as a proper fraction, improper fraction, or integer.
Submit

Answers

Answer:

-8.

Step-by-step explanation:

You can get the y-intercept when you find the y-value when x = 0.

y = x^2 - 8

y = 0^2 - 8

y = 0 - 8

y = -8

So, the y-intercept is -8.

Hope this helps!

Answer:

y = -8, if x2 mean 2 times x.

y = -7, if x2 mean X^2

Step-by-step explanation:

Y-intercept mean x = 0.

Plug x = 0, into the parabola, you get the answer.

A rectangle has the sides: 7cm and 3cm. A square has the same perimeter as the rectangle. What is the side length if the square

Answers

Answer:

5

Step-by-step explanation:

Perimeter of the rectangle: 3+7+3+7=20

Square perimeter is same as rectangle, so square perimeter is also 20.

Side length is 20/4, which is 5

The mean of 5,x,10,6,12 is 9. Find x

Answers

Answer:

12

Solution,

Summation FX= 5+10+6+12+X

=33+x

N(total no.of items)=5

Now,

Mean= summation FX/N

or 9=33+X/5

or 9*5=33+X ( cross multiplication)

or 45=33+X

or -x=33-45

or -x=-12

X=12

Hope this helps...

Good luck on your assignment..

Answer:

x = 12

Step-by-step explanation:

The mean calculated by adding all the numbers of a set and dividing it by the total number of numbers. In this case, we have five numbers, but we do not know what the sum of all the numbers is because one of the numbers in under the pronumeral x. The find this out we need to work backwards. We know that when all the five numbers are added we should get 45 (it is 9 time 5 as there are five numbers in the set). The next step is to subtract 45 from the number that we known (i.e. 45 - 5 - 10 - 6 - 12). This comes to 12.

To double-check if you got the right answer you could add all five numbers include the 12 and divide it by 5 to see if the answer is 9.

The height of a tree at time t is given by h(t) = 2t + 3, where h represents the height in inches and t represents the number of months. Identify the independent and the dependent variables.

Answers

Answer:

Step-by-step explanation:

You see that 't' is the 'argument' or 'input' to h:  h(t).  It is always safe to assume that t is the independent variable and h is the depend

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