A 5kg sample of plutonium-239 has a half-life of 21,400 years by emitting a 5.157 mev (million or mega electron volts) alpha particles. assume that the rate of decay is constant, how long will it take for the sample to degrade to 4.5kg?

Answers

Answer 1

Using an exponential function, it is found that it will take 3,252 years for the sample to degrade to 4.5kg.

What is the exponential function for the amount of a substance?

It is given by:

[tex]A(t) = Pe^{-kt}[/tex]

In which:

P is the initial amount. k is the decay rate, as a decimal.

The half-life is of 21,400 years, hence, A(21400) = 0.5P, and this is used to find k.

[tex]A(t) = Pe^{-kt}[/tex]

[tex]0.5P = Pe^{-21400k}[/tex]

[tex]e^{-21400k} = 0.5[/tex]

[tex]\ln{e^{-21400k}} = \ln{0.5}[/tex]

[tex]-21400k = \ln{0.5}[/tex]

[tex]k = -\frac{\ln{0.5}}{21400}}[/tex]

k = -0.00003239005

Hence, considering the initial mass is of P = 5 kg, the amount after t years is given by:

[tex]A(t) = 5e^{-0.00003239005t}[/tex]

The amount will be of 4.5 kg at t for which A(t) = 4.5, hence:

[tex]4.5 = 5e^{-0.00003239005t}[/tex]

[tex]e^{-0.00003239005t} = 0.9[/tex]

[tex]\ln{e^{-0.00003239005t}} = \ln{0.9}[/tex]

[tex]-0.00003239005t = \ln{0.9}[/tex]

[tex]t = -\frac{\ln{0.9}}{0.00003239005}[/tex]

t = 3252.

More can be learned about exponential functions at https://brainly.com/question/25537936

#SPJ1


Related Questions

#10 AH IM STUCK ON THIS ITS HARD HELP

Answers

Answer:

4.8 in

Step-by-step explanation:

feet to inch conversion is *12

2 * 12 = 24

then divide the scale (for every 1 in on the model there is 5 in on the actual, so divide the actual value by 5)

24/5 = 4.8

your answer is 4.8 in

hope this helps:)

Point C is on line segment \overline{BD}
BD . Given CD=2CD=2 and BD=17,BD=17, determine the length \overline{BC}.
BC .

Answers

Answer:

15

Step-by-step explanation:

The segment addition postulate states that if AC is a line with point B, then AB + CD must equal AC.

Setting Up the Equation

Using the postulate above we can set up an equation that is set equal to BD.

BC + CD = BD

Now, rewrite this using the information we are given in the question.

BC + 2 = 17

Solving For BC

Now, we can solve this equation using the properties of equality.

BC + 2 = 17

To solve you need to isolate BC. Do this by subtracting 2 from both sides.

BC = 15

This gives us the answer, 15.

Teenegers were asked how many times a week they were reminded to do chores. The responses are shown in the graph. What is the mean of the number of times per week that they were reminded?

Answers

Answer:

i could help but i don't see the graph chart

Step-by-step explanation:

Locate √13 √17 on number line. (Please step by step explanation or preferably done in notebook) I’ll mark brainless the best answer

Answers

Explanation:

Turn the irrational numbers into decimals, so it is easy to understand and point on the number line graph.

Numbers provided:

√13 = 3.605551275 ≈ 3.61

√17 = 4.123105625 ≈ 4.12

Step by Step Solving:

The number 3.61 will be between 3.5 and 3.7The number 4.12 will be between 4 and 4.2

Plot the points (circled area's):

In a normal distribution, 68% of the data fall within how many standard
deviations of the mean?
A. Two standard deviations
OB. One standard deviation
C. It cannot be determined from the given information.
D. Three standard deviations
← PREVIOUS
SURMIT

Answers

Using the Empirical Rule, the correct statement regarding where 68% of the data falls within the mean is given by:

B. One standard deviation.

What does the Empirical Rule state?

It states that, for a normally distributed random variable:

Approximately 68% of the measures are within 1 standard deviation of the mean.Approximately 95% of the measures are within 2 standard deviations of  the mean.Approximately 99.7% of the measures are within 3 standard deviations of the mean.

Hence option B is correct, as 68% of the data is within 1 standard deviation of the mean.

More can be learned about the Empirical Rule at https://brainly.com/question/24537145

#SPJ1

39. Find the probability of selecting a multiple of 2 or a
multiple of 7 from the integers 1-20.

Answers

The probability of selecting a multiple of 2 or a multiple of 7 is 11/20 or 0.55 or √0.3025.

What is probability?

It is defined as the ratio of the number of favourable outcomes to the total number of outcomes, in other words, the probability is the number that shows the happening of the event.

Total number of outcome = 20

Total number of favourable outcome (multiple of 2 or a multiple of 7):

E = {2, 4, 6, 7, 8, 10, 12, 14, 16, 18, 20}

n(E) = 11

The probability = 11/20 = 0.55 or

= √0.3025

Thus, the probability of selecting a multiple of 2 or a multiple of 7 is 11/20 or 0.55 or √0.3025.

Learn more about the probability here:

brainly.com/question/11234923

#SPJ1

Please help me with my math please?

Answers

Answer:

m = -1/3
b = 0
y = -1/3x

Step-by-step explanation:

The y-intercept is 0, so b is just 0. The slope of the line is 1/3 but it is decreasing not increasing, so it is negative. Then using the slope formula:
y = mx + b

y = -1/3x

(3,-2)(-3,2)

Slope:-

m=2+2/-3-3=4/-6=-2/3

Equation in point slope form

y+2=-2/3(x-3)3y+6=-2x+63y=-2xy=-2/3x

b=0

Type the correct answer in the box. polygon abcde is reflected across the x-axis to form polygon a′b′c′d′e′. then polygon a′b′c′d′e′ is dilated by a scale factor of 0.5 about d′ to form polygon lmnop. vertices a and b correspond to l and m, respectively. if the length of is 2.20 units, the length of is units. write your answer as a decimal number to two decimal places.

Answers

Based on the calculations, the length of LM is equal to 1.10 units.

Given the following data:

Scale factor = 0.5.

Length of AB = 2.20 units.

The types of transformation.

In Mathematics, there are different types of transformation and these include the following:

ReflectionRotationTranslationDilation

How to determine the length of LM?

Since polygon A'B'C'D'E' is dilated by using a scale factor of 0.5 about D', so as to form polygon LMNOP. Thus, the length of LM is given by:

LM = A'B' × scale factor

LM = 2.20 × 0.5

LM = 1.10 units.

Read more on dilation here: https://brainly.com/question/4040958

#SPJ4

Evaluate the indefinite integral.

Answers

Answer:

I believe its C , i took this class

Step-by-step explanation:

What is a name for the marked angle?

Answers

Answer:  [tex]\angle BAD[/tex]

Reason:

The arc goes from ray AB to ray AD. The two rays join at angle A which is the vertex point. When naming an angle, always use the vertex point in the middle. The order of the other two letters does not matter.

We could name this angle as [tex]\angle BAD[/tex] or [tex]\angle DAB[/tex] to mean the same exact thing. All that matters is that "A" is in the middle.

Ignore point C, and ignore ray AC entirely.

Answer:

  (b)  ∠BAD

Step-by-step explanation:

An angle can be named by the names of three points. The first point is on one of the rays that form the angle; the second point is the vertex; the third point is on the other ray.

Apparently the "marked" angle is identified by the arc extending from ray AB to ray AD. Point A is the vertex of the angle, so one possible name for it is ...

  ∠BAD

It can also be called

  ∠DAB

At Open Skate Night, admission is $3.75 with a membership card and $5.00 without a membership card. Skate rentals are $3.00.

The Moores paid $6 more for skate rentals than the Cotters did. Together, the two families paid $24 for skate rentals.

How many pairs of skates did the Moores rent?

The Moores rented pairs of skates.

Answers

Answer:

15 dollars and they got 2 more pairs than the cotters. hope this helps.

| Jill was given $175 but her mother was given five times as
much. How much was her mother given?

Answers

The answer is $875 !!

Answer:

$875

Step-by-step explanation:

Jill was given $175 and her mother was given 5 times the amount.

Multiply 175 and 5.

Amount for mother = $175 x 5Amount for mother = $875

a birthday cake is divided equally between 9 people what fraction of the cake does each person have?

Answers

i am pretty sure it is 1/9 because each person gets a piece of the cake and if there are 9 people there are 9 pieces.

[tex]\rule{300}{1}\\\dashrightarrow\large\blue\textsf{\textbf{\underline{Given question:-}}}[/tex]

  A birthday cake is divided equally between 9 people.

What fraction of the cake does each person have?

[tex]\dashrightarrow\large\textsf{\textbf{\underline{\underline{Answer and How to solve:-}}}}[/tex]

[tex]\ast[/tex] Remember, a fraction looks like:-

[tex]\boxed{\frac{\xrightarrow{numerator}x}{\xrightarrow{denominator}{y}}}[/tex]

Where:-

numerator -> number of parts takendenominator -> total parts

In this case we divide a cake equally between 9 people, so we divide the cake into 9 parts, and each person gets a part of the cake.

So we have a fraction as follows:-

[tex]\dfrac{?}{9}[/tex]

Now, each person gets 1 part. 1 becomes our numerator:-

[tex]\dfrac{1}{9}[/tex]

[tex]\uparrow\sf{Our\:Answer}[/tex]

Good luck with your studies.

[tex]\rule{300}{1}[/tex]

X^2-11x+24
I need to convert the quadratic equation from expanded to factored form

Answers

Answer:

[tex](x - 3) \: (x - 8)[/tex]

Step-by-step explanation:

We were given the equation:

[tex] {x}^{2} - 11x + 24 = 0[/tex]

Therefore in order to factorize we first need to find the numbers that add to be equal to -11 and multiply to be equal to 24. The two numbers are:

[tex] - 8 \: and \: - 3 \\ \\ - 8 + ( - 3) = - 11 \\ - 8 \times - 3 = 24[/tex]

So the new equation is

[tex]{x}^{2} - 8x - 3x + 24 = 0 \\ \\ factorize: ( {x}^{2} - 8x) \: ( - 3x + 24) = 0 \\ \\ x(x - 8) \: - 3(x - 8) \\ \\ therefore : (x - 3) \: ( x - 8) = 0[/tex]

Answer:

Step-by-step explanation:

Comment

There are a lot of choices. Luckily the middle term is minus and the third term is plus, so you don't have to juggle minus signs around. Both factors are minus when put together with x.

-3 - 8

-4 - 6

-2 -12

-1 - 14

I think these are all the possible factors.

-4 + - 6 = - 10  Not the answer. It needs to be - 11

-2 + -12 = -14  Not the answer. It needs to be - 11

-1 + - 24 = -25 Just about as far away as you can get. Not the answer

So A must be right

-3 + -8 = - 11

That's what it should be. So the factors are

Answer:

(x -3)(x - 8)= x^2 - 11x + 24

Using the points ( 6.4, 117) and (6.6, 120), what is the slope of the trend line?
a. -15
b. -12
c. 12
d. 15

Answers

Answer:

d 15.

Step-by-step explanation:

Slope = (difference in y values)/ (corresponding difference in x values)

So we have:

Slope = (120-117)  / (6.6-6.4)

          =  3 / 0.2

           = 30/2 = 15.

Directions: Using the digits 0-9, no more than once each, fill in the boxes to make the statement true:

Answers

The equation [tex]\frac{5-3-2}{1+4+6+7+8+9}[/tex]  = 0 is true

What is fraction?

In arithmetic, a number expressed as a quotient, in which a numerator is divided by a denominator.

Using digits 0 to 9, no more than once each.

we want to place them in such a way that the division will be zero.

As we know that a quotient is equal to zero iff the numerator is equal to zero and the denominator other than zero.

So if we put some numbers on the numerator in such a way by adding them gives 0.

So, 5 - 3 - 2 = 0

Use all the other numbers in the denominator.

[tex]\frac{5-3-2}{1+4+6+7+8+9}[/tex]  = 0

which is true.

Learn more about percentage here:

https://brainly.com/question/15305561

#SPJ1

PLEASE HELP ME FIND THE INEQUALITY SIGN OF THESE PROBLEMS

Answers

Answer:

2.5 > 2 2/5

Step-by-step explanation:

2 2/5 = 2.4

2.4 is less than 2.5

. Find the area of a circle with a
circumference
of 11( 3.14 )

feel
?

Answers

Answer:

95.03

Step-by-step explanation:

Use the table below to answer this question:

x y
−1
7
3
3
5
1
Find the average rate of change for the given function from x = −1 to x = 5. (5 points)

−6
−1
1
6

Answers

Using it's concept, it is found that the average rate of change of the function from x = -1 to x = 5 is of -1.

What is the average rate of change of a function?

It is given by the change in the output divided by the change in the input.

In this problem, the output changes by -6(from 7 to 1) when the input changes by 6(from -1 to 5), hence the average rate is given by:

r = -6/6 = -1.

More can be learned about the average rate of change at https://brainly.com/question/24313700

#SPJ1

please help with this!

Answers

Answer:

3/8

Step-by-step explanation:

1/8 + 1/4 = 1/8 + 2/8 = 3/8

Note that 1/4 = 1/4 * 2/2 = 1*2 / 4*2 = 2/8

A company decides to mix pinapple and orange soda to make a new drink.
They have 450 liters of pinapple soda, which is 42% sugar.
They mix it with 630 liters of orange soda.
The new drink is 35% sugar.
What percentage of the orange soda is sugar?

Answers

42% of 450 litres = 189 litres
450l+630l=1080l
189/1080x100=17.5
35-17.5=17.5
Orange soda has 17.5% sugar.

Which represents the inverse of the function f(x) =4x?

Answers

Let's see

Let y=f(x)

y=4x

Intechange x and y

x=4y

Find y

y=x/4

The inverse is y=x/4

Graphs attached

Answer:

[tex]\sf f^{-1}(x)=\dfrac{x}{4}[/tex]

Step-by-step explanation:

The inverse of a function is the reflection of the function in the line y = x

To find the inverse of a function:

Set the function to y:

⇒ y = 4x

Make x the subject:

[tex]\sf \implies x=\dfrac{y}{4}[/tex]

Change x to [tex]\sf f^{-1}(x)[/tex] and y to x:

[tex]\sf \implies f^{-1}(x)=\dfrac{x}{4}[/tex]

What is the Volume! ~

Answers

Answer:

108

Step-by-step explanation:

Volume of a Square Pyramid :

V = 1/3 x Base Area x Height

Solving :

V = 1/3 x (6)² x 9V = 36 x 3V = 108 cubic centimeters

Answer: Volume = 108 cm ³

Explanation:

For a square pyramid, the volume can be calculated as follows:

Volume =  * area of base * height

Volume =  * side² * height

We have:

side length = 6 cm

height = 9 cm

Therefore:

Volume =  * 36 * 9 = 108 cm ³

Hope this helps :)

Thomas found a box that had a volume of 150 in3. He measured the height of the box to be 2 inches and the length was 10 inches more than the width. What is the width of the box?

Answers

The width of the rectangular box with  volume of 150 cubic inches is: 5 inches.

What is the Volume of a Box?

Volume of a box = (length)(width)(height).

Given the following:

Volume of the box = 150 in.³Height = 2 in.Width = w in.Length = w + 10 in.

150 = (w + 10)(w)(2)

2w² + 20w - 150 = 0

Factorize

(w - 5)(w + 15) = 0

w = 5, w = -15

The width cannot be negative, therefore, the width of the box is: 5 inches.

Learn more about the volume of a box on:

https://brainly.com/question/14957364

#SPJ1

(URGENT) Maurice and Rhonda a are traveling in the same direction along the same road. Maurice is traveling at 55 mph and is exactly 15 miles ahead of Rhonda, who is traveling at 65 mph. How many hours will it take Rhonda to catch Maurice?

Answers

Answer:

Step-by-step explanation:

Givens

Maurice

55 miles an hour

15 miles ahead of Rhonda

d1

Rhonda

65 miles per hour

d2

The distance has to be the same for both in order to meet.

Formula

d1 = d2

d = r * t                                   where r is the speed.

65*t = 55t + 15                       Subtract 55t from both sides

Solution

65t - 55t = 55t - 55t + 15       Combine

10t = 15                                    Divide both sides by 10

10t/10 = 15t/10            

t = 1.5 hours

Answer

They will meet in 1.5 hours.


3. Juan makes $9.00 per hour and works 30 hours per week. If Juan has $70 deductions, what is his
Net income?

Answers

Answer:

$200

Step-by-step explanation: You take $9.00 and multiply it by 30 and then you take whatever that answer is and subtract 70 from it to get the net income

The increase in a person’s body temperature t(t), above 98.6ºf, can be modeled by the function t (t) = startfraction 4 t over t squared 1 endfraction, where t represents time elapsed. what is the meaning of the horizontal asymptote for this function?

Answers

The person's body temperature will approach 98.6ºF as time lapses,  The horizontal asymptote of y = 0 means that the person’s temperature will approach 98.6ºF as time elapses.

What is horizontal asymptote?

A horizontal asymptote is  known to be that line that is  horizontal in nature and it is one that is not an aspect of a graph that has a function but t act as a guides for its x-values.

Note that Horizontal asymptote occurs to T(f) only when t is said to be very large (as it approaches infinity) and thus, it connote that the person's body temperature will be going towards 0ºF above 98.6ºF as t moves to infinity.

See full question below

The increase in a person’s body temperature T(t), above 98.6ºF, can be modeled by the function T(t)=(4t)/(t^2 +1), where t represents time elapsed. What is the meaning of the horizontal asymptote for this function?

The horizontal asymptote of y = 0 means that the person’s temperature will approach 98.6ºF as time elapses. The horizontal asymptote of y = 0 means that the person’s temperature will approach 0ºF as time elapses. The horizontal asymptote of y = 4 means that the person’s temperature will approach 102.6ºF as time elapses. The horizontal asymptote of y = 4 means that the person’s temperature will approach 4ºF as time elapses.

Learn more about temperature from

https://brainly.com/question/2368049

#SPJ4

10. In a sale, the price of a digital camera is reduced by 18%.
The new price of the camera is £287.
(a) Work out the price of the camera before the sale

Answers

Answer:

£350

Step-by-step explanation:

287/0.82

HELP can i get some help here please

Answers

The graph of the system of inequalities can be seen at the end of the answer.

How to graph the system of inequalities?

Here we have two inequalities:

x < 2

y ≥ - 3

To graph the first one, we need to shade all the region at the left of the line x = 2, such that the line must be dashed, because the points on the line are not solutions.

For the second inequality, we need to shade all the regions above the line y = -3, this time the line must be solid, because the points on the line are solutions.

Then the graph of the inequalities is the one you can see below. The intersection of the shaded regions is the solution of the system of inequalities.

If you want to learn more about inequalities:

https://brainly.com/question/18881247

#SPJ1

On Tuesday 1/3 of students were absent. Thursday 1/9 were absent. If 20 more students were absent on Tuesday than Thursday, how many students are there in the school? ​

Answers

Answer:

There are 90 students in this school.

Step-by-step explanation:

Answer:

90 students are in the class

Step-by-step explanation:

So basically, you need to make this ration fraction equation:

[tex]\frac{1}{3} \\\\[/tex]  - [tex]\frac{1}{9} \\[/tex] = 20 .

you would come up with 2/9 is 20.

Times it by both sides and you will get 180=2x.

Note this x is added so you will get a variable and not get confused.

Then, your answer would become x=90.

Other Questions
Explain how to derive a formula for sin(A - B + C) what is 750 grams of phosphorus What is the mineral formerly used for fireproofing and insulation that can cause lung damage when inhaled?asbestosfoam-boardfiberglasslead Write .0043 as a percentage What goals did the delegates have at the start of the Philadelphia Convention? Finley is trying to transmit a sound wave that will travel continuously, but he is frustrated by the excess noise. what kind of signal is finley sending? analog digital radio infrared For the complex number z=5sqrt3/4 - 5/4i, what is the polar form? why is the hiv virus the most challenging virus in the last 40 years? The weak form of the efficient market hypothesis implies that:________ a) No one can achieve abnormal returns using market information. b) Insiders, such as specialists and corporate board members, cannot achieve abnormal returns on average. c) Investors cannot achieve abnormal returns, on average, using technical analysis, after adjusting for transaction costs and taxes. d) All of above. Why do you think the Indians were not employed by the British for higher positions The provided map shows the location of an earthquake under the ocean.The data on the map would best support a prediction of which of the following events?O A tsunami in Sri LankaO An earthquake in South AfricaO A hurricane in SomaliaO Flash floods in Madagascar Please answer for me, image below. Thanks! Explain the levels of organization beyond our planet. Mr harris wants to know if the new tardy policy is effective how can he find out without using a biased survey For questions 1-2, use the Reciprocal and Quotient Identities to find each value. simultaneous equations please someone help me2x +5y = -10 2x -y =8 3.7 Code Practicecan someone write a code for me What did Benki teach his people? Is quartzite a mineral, a rock, or neither? What is the role of pressure and dissolved gases in eruptions?.