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
zimovet [89]
3 years ago
9

A Geiger counter registers a count rate of 8,000 counts per minute from a sample of a radioisotope. The count rate 24 minutes la

ter is 1,000 counts per minute. What is the half-life of the radioisotope?
Physics
1 answer:
zmey [24]3 years ago
4 0

11.54 minutes

Explanation:

The decay rate equation is given by

N = N_0e^{-\frac{t}{\lambda}}

where \lambda is the half-life. We can rewrite this as

\dfrac{N}{N_0} = e^{-\frac{t}{\lambda}}

Taking the natural logarithm of both sides, we get

\ln \left(\dfrac{N}{N_0}\right) = -\left(\dfrac{t}{\lambda}\right)

Solving for \lambda,

\lambda = -\dfrac{t}{\ln \left(\frac{N}{N_0}\right)}

\:\:\:\:= -\dfrac{(24\:\text{minutes})}{\ln \left(\frac{1000\:\text{counts/min}}{8000\:\text{counts/min}}\right)}

\:\:\:\:=11.54\:\text{minutes}

You might be interested in
A Rankine oval is formed by combining a source-sink pair, each having a strength of 36 ft2/s and separated by a distance of 15 f
Rashid [163]

Answer:

0.28 ft

Explanation:

We are given that

Strength=m=36ft^2/s

Distance between source and sink=15 ft

Distance between the sink of the source and origin=a=\frac{15}{2} ft

Uniform velocity, U=12 ft/s

We have to find the length of the oval.

Formula to find the half length of the body

\frac{l}{a}=(\frac{m}{\pi Ua}+1)^{\frac{1}{2}}

Where a=Distance between sink of source and origin

U=Uniform velocity

m=Strength

l=Half length

Using the formula

\frac{l}{\frac{15}{2}}=(\frac{36}{\pi\times 12\times \frac{15}{2}}+1)^{\frac{1}{2}}

l=\frac{2}{15}(\frac{36}{\pi\times 12\times \frac{15}{2}}+1)^{\frac{1}{2}}

l=0.14

Length of oval=2l=2(0.14)=0.28 ft

8 0
3 years ago
Please help with both will give brainlist worth 20
REY [17]

Answer:

Second bubble

Explanation:

Its going up

7 0
3 years ago
A 1.83 kg book is placed on a flat desk. Suppose the coefficient of static friction between the book and the desk is 0.442 and t
fredd [130]

Answer:7.92 N

Explanation:

Given

mass of book m=1.83\ kg

coefficient of static friction \mu _s=0.442

coefficient of kinetic friction \mu _k=0.240

To move the book, one need to overcome  the static friction  

Static friction F_s=\mu _sN

F_s=\mu _s\times 1.83\times 9.8

F_s=0.442\times 1.83\times 9.8

F_s=7.92\ N

After overcoming the Static friction , Force needed to move the block is

F_k=\mu _kN

F_k=0.240\times 1.83\times 9.8

F_k=4.30\ N

8 0
3 years ago
A hockey puck has a momentum of 3.8 kg•m/s [E]. If its
agasfer [191]

Answer:

1.6 \times 10 { }^{ - 1} kg \\

Explanation:

I hope, it helped you.

4 0
3 years ago
This is my question. I need the answer stat.
Kipish [7]

Answer:

Explanatioyour answers look right, but if there has , has to be another answer its a , but your answers are right

5 0
3 years ago
Read 2 more answers
Other questions:
  • A block measure 10 cm by 10 cm by 5 cm , what is it’s volume
    9·1 answer
  • Which types of heat transfer that allows heat to flow from hot objects to colder object? A. convection, but not conduction or ra
    10·1 answer
  • 2. Who were the first philosophers to propose that atoms existed? What time period was<br> this?
    7·1 answer
  • How much heat is absorbed by a 43g iron skillet when its temperature rises from 8oC to 28oC?
    10·1 answer
  • When two waves are moving toward each other, and their crests line up with each other, it results in a wave with greater amplitu
    6·1 answer
  • What happens when matter and antimatter collide
    15·1 answer
  • In every atom, one or more positive charges are positioned ______.
    6·1 answer
  • Discuss the negative consequences of the global dependence on fossil fuels.
    10·1 answer
  • Calculate the momentum for each ocean creature and then answer the question. A 500 kg dolphin swims at 4 m/s. A 700 kg sea turtl
    15·2 answers
  • What is the electric field 4.0 m from the center of the terminal of a Van de Graaff with a 7.10 mC charge, noting that the field
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!