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
Zinaida [17]
3 years ago
12

carbon-14 has a half-life of approximately 5,700 years. a fossil shell contain 25% of the original amount of its carbon-14. appr

oximately how many years ago was this shell part of a living oranism?
Physics
1 answer:
denis23 [38]3 years ago
3 0

The half-life equation m=m_{0} (\frac{1}{2})^n in which <em>n </em>is equal to the number of half-lives that have passed can be altered to solve for <em>n.</em>

<em>n = \frac{log(\frac{m}{m_{0}} )}{log(\frac{1}{2})}</em>

<em>\frac{log(\frac{.25}{1} )}{log(\frac{1}{2})} = 2</em>

Then, the number of half-lives that passed can be multiplied by the length of a half-life to find the total time.

<em>2 * 5700 =  </em>11400 yr

You might be interested in
Thermopane window is constructed, using two layers of glass 4.0 mm thick, separated by an air space of 5.0 mm.
Bond [772]

To solve this problem it is necessary to apply the concepts related to rate of thermal conduction

\frac{Q}{t} = \frac{kA\Delta T}{d}

The letter Q represents the amount of heat transferred in a time t, k is the thermal conductivity constant for the material, A is the cross sectional area of the material transferring heat, \Delta T, T is the difference in temperature between one side of the material and the other, and d is the thickness of the material.

The change made between glass and air would be determined by:

(\frac{Q}{t})_{glass} = (\frac{Q}{t})_{air}

k_{glass}(\frac{A}{L})_{glass} \Delta T_{glass} = k_{air}(A/L)_{air} \Delta T_{air}

\Delta T_{air} = (\frac{k_{glass}}{k_{air}})(\frac{L_{air}}{L_{glass}}) \Delta T_{glass}

\Delta T_{air} = (\frac{0.84}{0.0234})(\frac{5}{4}) \Delta T_{glass}

\Delta T_{air} = 44.9 \Delta T_{glass}

There are two layers of Glass and one layer of Air so the total temperature would be given as,

\Delta T = \Delta T_{glass} +\Delta T_{air} +\Delta T_{glass}

\Delta T = 2\Delta T_{glass} +\Delta T_{air}

20\°C = 46.9\Delta T_{glass}

\Delta T_{glass} = 0.426\°C

Finally the rate of heat flow through this windows is given as,

\Delta {Q}{t} = k_{glass}\frac{A}{L_{glass}}\Delta T_{glass}

\Delta {Q}{t} = 0.84*24*10 -3*0.426

\Delta {Q}{t} = 179W

Therefore the correct answer is D. 180W.

3 0
3 years ago
A SMALL cup of tea has water inside that is very hot, about 80 degrees Celsius. A LARGE bathtub has water inside it that is warm
Artist 52 [7]

Answer:

the water in the tea cup

Explanation:

Kinetic energy is the energy an object or particles possesses as a result of motion.

Liquid in higher temperature possesses more kinetic energy than liquid with lower temperature

7 0
3 years ago
Which statements about Earth’s core help explain Earth’s magnetic field? Check all that apply.
Stella [2.4K]

All the statements can be used to explain about Earth's magnetic field.

Earth's magnetic field is almost same to that of the bar magnet. The magnetic field of the earth occurs from its core. It has an inner core which is solid in nature. in the outer core, there is a motion of the liquid due to heat flow from the inner core to the core mantle boundary which proves that the outer core is liquid and moving. The Earth's core consists of iron and nickel as the Eddy currents in the iron and nickel liquid helps generating the Earth's magnetic field.

Hence, all the three statements are true and can be used to explain the Earth's magnetic field.

5 0
4 years ago
Read 2 more answers
2 Points
Mademuasel [1]

According to Newton's Second Law of Motion :

The Force acting on an Object is equal to Product of Mass of the Object and Acceleration produced due to the Force.

:\implies  Force acting = Mass of the Object × Acceleration

Given : Force = 50 newton and Mass of the Object = 10 kg

Substituting the respective values in the Formula, we get :

:\implies  50 N = 10 kg × Acceleration

:\implies \mathsf{Acceleration = \dfrac{50\;N}{10\;kg}}

:\implies Acceleration of the Object = 5 m/s²

4 0
4 years ago
Which statement BEST describes Miguel Hidalgo?
tatiyna
Miguel Hidalgo was a Priest so I think it would be 1. 
Hope I Helped ( : 
6 0
3 years ago
Read 2 more answers
Other questions:
  • An equilateral triangle 8.0 cm on a side is in a 3.5 mT uniform magnetic field. The magnetic flux through the triangle is 6.0 μW
    14·1 answer
  • At a distance D from a very long (essentially infinite)uniform line of charge, the elecric field is 1000 N/C. Forthe field stren
    9·2 answers
  • Kepler discovered that _____ have elliptical orbits.
    15·2 answers
  • Nitromethane (ch3no2) burns in air to produce significant amounts of heat. 2 ch3no2(l) + 3 2 o2( g) ¡ 2 co2( g) + 3 h2o(l) + n2
    5·2 answers
  • A 206.3 kg walrus initially at rest on a horizontal floor requires a 249 N horizontal force to set it in motion. Find the coeffi
    15·1 answer
  • The total energy in a system is 675 J. The kinetic energy changes from 296 to 432 J. Which statement best describes the potentia
    6·2 answers
  • A machine can multiply forces for
    8·1 answer
  • A 200 kg car is travelling at 33m/s. what is the kinectic energy of the car​
    5·2 answers
  • When 1.5 kg of mass turns into energy, how much energy is released? Find the equation, substitution, and number with units.
    14·1 answer
  • What factor contributes most to the kinetic energy of a body in motion
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!