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
irga5000 [103]
3 years ago
11

Strontium 3890Sr has a half-life of 28.5 yr. It is chemically similar to calcium, enters the body through the food chain, and co

llects in bones. Consequently, 3890Sr is a particularly serious health hazard. How long (in years) will it take for 99.99% of the 3890Sr released in a nuclear reactor accident to disappear?
Physics
1 answer:
patriot [66]3 years ago
5 0

Answer:

Thus the time taken is calculated as 387.69 years

Solution:

As per the question:

Half life of ^{3890}Sr\, t_{\frac{1}{2}} = 28.5 yrs

Now,

To calculate the time, t in which the 99.99% of the release in the reactor:

By using the formula:

\frac{N}{N_{o}} = (\frac{1}{2})^{\frac{t}{t_{\frac{1}{2}}}}

where

N = No. of nuclei left after time t

N_{o} = No. of nuclei initially started with

\frac{N}{N_{o}} = 1\times 10^{- 4}

(Since, 100% - 99.99% = 0.01%)

Thus

1\times 10^{- 4} = (\frac{1}{2})^{\frac{t}{28.5}}}

Taking log on both the sides:

- 4 = \frac{t}{28.5}log\frac{1}{2}

t = \frac{-4\times 28.5}{log\frac{1}{2}}

t = 387.69 yrs

You might be interested in
Which best supports the idea that the surface of the moon has changed very little?
nasty-shy [4]
<span>Because the moon has no atmosphere, it is not possible for geologic events to occur on the moon.</span>
4 0
3 years ago
Read 2 more answers
a typical cmall flashlight contains two batteries each having na emf of 2.0 v connected in series with a bulb havin ga resistanc
Helen [10]

Answer:

P = 0.25 W

Explanation:

Given that,

The emf of the battry, E = 2 V

The resistance of a bulb, R = 16 ohms

We need to find the power delivered to the bulb. We know that, the formula for the power delivered is given by :

P=\dfrac{V^2}{R}\\\\P=\dfrac{2^2}{16}\\\\=0.25\ W

So, 0.25 W power is delivered to the bulb.

5 0
3 years ago
In freefall, heavier objects fall with a greater acceleration than lighter objects.
Rom4ik [11]

Answer:

That is not true all objects fall at the same speed excepts things like feathers or paper.

6 0
3 years ago
Read 2 more answers
our iclicker operates at a frequency of approximately 900 mhz (900x106 hz). what is the approximate wavelength of the em wave pr
Elena-2011 [213]

wavelength of the EM  wave produced by your iclicker is 0.33 m.

<h3>What makes an EM wave?</h3>
  • When an electric field (illustrated in red arrows) combines with a magnetic field, electromagnetic waves are generated (which is shown in blue arrows). An electromagnetic wave's magnetic and electric fields are perpendicular to each other and to the wave's direction.
  • A changing magnetic field causes a changing electric field, and vice versa—the two are inextricably related. Electromagnetic waves are created by changing fields. Electromagnetic waves, unlike mechanical waves, do not require a medium to propagate.

The clicker emits EM (electromagnetic) wave which travels at the speed of light, that is

v = 3 x 10⁸ m/s

The frequency is

f = 900mHz = 9 x 10⁸ Hz

velocity = frequency * wavelength, the wavelength, λ,  is given by

fλ = v

λ = v/f

  = (3 x 10⁸ m/s) / (9 x 10⁸ 1/s)

  = 1/3 m = 0.333 m

To learn more about   electromagnetic waves  refer,

brainly.com/question/25847009

#SPJ1

6 0
1 year ago
At a sudden contraction in a pipe the diameter changes fromD1toD2. The pressure drop,Δp, which develops across the contraction i
Sever21 [200]

Answer: The working and answer can be viewed from the screenshots below. Thanks

5 0
3 years ago
Other questions:
  • A turtle takes 3.5 minutes to walk 18 m toward the south along a deserted highway. A truck driver stops and picks up the turtle.
    11·1 answer
  • A 10-kg dog is running with a speed of 5.0 m/s. what is the minimum work required to stop the dog in 2.40 s?
    7·1 answer
  • Graphs are representations of equations.<br> A. True<br> B. False
    5·2 answers
  • find the average velocity of a bicycle that starts 100km south and is 120km south of town after 0.4 hours​
    12·1 answer
  • What does the atomic number tell us about an atom of a certain element?
    5·1 answer
  • three small balls each of mass 13.3g are suspended separately from a common point by silk threads, each 1.17m long. The balls ar
    10·1 answer
  • Help me pls I WILL GIVE BRAINIEST I DONT CARE PLS HELP
    6·2 answers
  • 1) Find the L.C.M. of 24, 60 and 96.​
    8·2 answers
  • A ball rolls up a ramp with a velocity of 8.0 m/s. How high up the ramp does it travel?
    8·1 answer
  • Which class of hazards is characterized by thermal and mechanical hazards in the form of blast pressure waves, shrapnel and frag
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!