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
SCORPION-xisa [38]
4 years ago
12

Help with a and b? I don't understand how to do it

Physics
1 answer:
ZanzabumX [31]4 years ago
5 0
A).  If the half-life is 40 days, then 5 half-lives = (5 x 40) days.

b).  If 5 half-lives have passed, then the radioactive portion of
the sample has been cut in half five times.

The amount that remains is  (1/2)⁵ of the original amount.

That's (the original amount) x (1/2 · 1/2 · 1/2 · 1/2 · 1/2)
or
           (the original amount) / 2⁵
or
           (the original amount) / 32 .
You might be interested in
Are volcanoes fed by highly viscous magma a greater threat to life and property than volcanoes supplied with very fluid magma?
butalik [34]

Answer:

A volcano fed by highly viscous magma is likely to be a greater threat to life and property than a volcano supplied with very fluid magma because with high viscous magma gas is trapped more in the magma so the gas will build up and then eventually explode, whereas with fluid magma the gas can escape allowing the magma.

HOPE THIS HELPS!!!

Explanation:

3 0
3 years ago
Explain how the planets in the solar system formed
Fed [463]
<span>So we want to know how did the planets form in the Solar system. So the current most accepted explanation is accretion. First the Sun formed, and what has left was a disk made out of gas and dust which later formed the planets trough attractive gravitational force.</span>
6 0
3 years ago
Explain the difference between balanced forces and action and reaction forces.
Monica [59]
Action-reaction forces<span> act on different objects; </span>balanced forces<span> act on the same object. </span>Balanced forces<span> can result in acceleration, </span>action-reaction forces<span> cannot. ... Newton's Third Law of Motion does not apply to </span>balanced forces<span>.</span>
5 0
3 years ago
A. What are the three longest wavelengths for standing waves on a 240-cm-long string that is fixed at both ends?
vovangra [49]

Answer:

a) the three longest wavelengths = 4.8m, 2.4m, 1.6m

b) what is the frequency of the third-longest wavelength = 75Hz

Explanation:

The steps and appropriate formula and substitution is as shown in the attached file.

5 0
3 years ago
A bottle lying on the windowsill falls off and takes 4.95 seconds to reach the ground. The distance from the windowsill to the g
mr Goodwill [35]

The distance an object falls from rest through gravity is

                         D  =  (1/2) (g) (t²)

            Distance  =  (1/2 acceleration of gravity) x (square of the falling time)

We want to see how the time will be affected
if  ' D ' doesn't change but ' g ' does.
So I'm going to start by rearranging the equation
to solve for ' t '.

                                                      D  =  (1/2) (g) (t²)

Multiply each side by  2 :         2 D  =            g    t² 

Divide each side by ' g ' :      2 D/g =                  t²

Square root each side:        t = √ (2D/g)


Looking at the equation now, we can see what happens
to ' t ' when only ' g ' changes: 

-- ' g ' is in the denominator; so bigger 'g' ==> shorter 't'
                                             and smaller 'g' ==> longer 't' .

-- They don't change by the same factor, because  1/g  is inside
the square root.  So 't' changes the same amount as  √1/g  does.

Gravity on the surface of the moon is roughly  1/6  the value
of gravity on the surface of the Earth.

So we expect ' t ' to increase by  √6  =  2.45 times.

It would take the same bottle  (2.45 x 4.95) = 12.12 seconds
to roll off the same window sill and fall 120 meters down to the
surface of the Moon.
4 0
3 years ago
Read 2 more answers
Other questions:
  • The number of protons and neutrons in an atom is that atom’s _____________ number.
    7·2 answers
  • Un espejo convexo y un cóncavo tienen la misma distancia radial igual a 5m. La separación entre espejos es de 3 veces la distanc
    5·1 answer
  • Even if it is wrong, why is a hypothesis important?
    11·1 answer
  • A common, though incorrect, statement is, "The Moon orbits the Earth." That creates an image of the Moon?s orbit that looks like
    7·1 answer
  • Help Please
    5·1 answer
  • When you whirl a small rubber stopper on a cord in a vertical circle, you find a critical speed at the top for which the tension
    12·1 answer
  • Use the f=ma formula to determine your weight in newtons AND pounds on the Moon and Pluto you have a mass of 70.3 kilograms
    8·1 answer
  • An oil tank has a base of area 2.5 m2 and is filled with oil to a depth of 1.2 m. The density of the
    15·1 answer
  • a disk of a radius 50 cm rotates at a constant rate of 100 rpm. what distance in meters will a point on the outside rim travel d
    10·1 answer
  • A cannonball is fired from a cliff that is 50 meters above the ground. The cannonball is fired horizontally with a speed of 120
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!