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
Julli [10]
3 years ago
5

The concentration of an isotope is 1/500 of its initial value after one day. What is the rate of decay?

Physics
1 answer:
mel-nik [20]3 years ago
8 0
The exponential growth/decay formula is given by A = Pe^(rt), where A is the final amount, P is the initial amount, r is the rate of growth/decay and t is time. 

We are given A = (1/500)P and t=1, so substituting:
(1/500)P = Pe^(r*1)
Cancelling out P on both sides:
1/500 = e^r
ln(1/500) = ln(e^r)
r = -6.215

Rate of decay is -6.215 per day.
You might be interested in
A rectangular sharp-crested weir is contracted on both sides, and the opening is 1.2 m wide. At what height (Hw) should it be pl
Alex

Answer:

H_w = 2.129 m

Explanation:

given,

Width of the weir, B = 1.2 m

Depth of the upstream weir, y = 2.5 m

Discharge, Q = 0.5 m³/s

Weir coefficient, C_w = 1.84 m

Now, calculating the water head over the weir

Q = C_w BH^{3/2}

H = (\dfrac{Q}{C_wB})^{2/3}

H = (\dfrac{0.5}{1.84\times 1.2})^{2/3}

H = 0.371\ m

now, level of weir on the channel

H_w = y - H

H_w = 2.5 - 0.371

H_w = 2.129 m

Height at which weir should place is equal to 2.129 m.

7 0
3 years ago
An object has a mass of 7 kg and is accelerating at 4 m/s2. How far would the object move if it took 168 J of work to move it?​
KIM [24]

Answer:

6m

Explanation:

use work =force×distance

6 0
3 years ago
Action-reaction forces are not balanced forces because of what?
lara [203]

Oh but they are !

Newton's 3rd law of motion says that for every action, the <em><u>re</u></em>action is
equal and opposite.  That's as balanced as you can get.


4 0
3 years ago
What is gravity?what is one solar day?<br>​
mafiozo [28]

Answer:

<h2>Gravity :</h2><h3>the force that attracts a body towards the centre of the earth, or towards any other physical body having mass.</h3>

<h2>Solar day</h2><h3>A solar day is the time it takes for the Earth to rotate about its axis so that the Sun appears in the same position in the sky.</h3><h2> or</h2><h3>It is the time between successive meridian transits of the sun at a particular place.</h3>
6 0
3 years ago
A backpacker walks for 3 days in the mountains and covers 16 km. How fast was he walking in km/hr?
Fudgin [204]

Answer:

0.22 km/h

Explanation:

72 hours in 3 days

16/72 = 0.222222222

round to 0.22 km/h

For future reference, Distance/Time= Speed

5 0
3 years ago
Other questions:
  • How many air molecules are in a 14.0×12.0×10.0 ft room? assume atmospheric pressure of 1.00 atm, a room temperature of 20.0 ∘c,
    12·2 answers
  • What’s is a object that moves through the air space acted on only by gravity
    5·2 answers
  • A very long, solid cylinder with radius R has positive charge uniformly distributed throughout it, with charge per unit volume \
    9·1 answer
  • What is the relationship between the kinetic energy of molecules in an object and the object's temperature?
    5·2 answers
  • The spherical side mirror on a car is convex and has a radius of curvature of 25 cm. Another car is following, 20 m behind the m
    6·1 answer
  • What is the average temperature of the city, 89.6 Fahrenheit, on the Celsius scale?
    7·1 answer
  • Topic: Chapter 10: Projectory or trajectile?
    13·1 answer
  • How is the oxygen level of blood related to its color?
    5·1 answer
  • A boy pushes a 50 kilogram wagon with a force of 4 N east while an orangutan pushes the wagon
    5·1 answer
  • Metallic gold crystallizes in a face-centered cubic lattice, with one au atom per lattice point. if the edge length of the unit
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!