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Hunter-Best [27]

3 years ago

14

Testing shows that a sample of wood from an artifact contains 12.5% of the original amount of carbon-14. Given that the half-lif

e of carbon-14 is 5730 years, how old is the artifact?
A. 22,920 years
B. 17,190 years
C. 11,460 years
D. 5730 years

2 answers:

castortr0y [4]3 years ago

7 0

Answer: i think

Explanation:

d

ratelena [41]3 years ago

5 0

Answer:

B. 17,190 (A P E X)

Explanation:

If the half-life of carbon-14 is 5730 years then for every 5730 years the original amount of the carbon-14 is cut in half. So if it originally started at 100% when it was new then in 5730 years it would drop to 50%. After that, every 5730 years it drops to 25% and then 12.5% and so on.

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Calculate the force between two objects that have masses of 70 kilograms and 2,000 kilograms separated by a distance of 1 meter.

Makovka662 [10]

$▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪$

The Gravitational Force between given objects will be ~

$9.34 \times {10}^{ - 6} \: \: N$

$\large \boxed{ \mathfrak{Step\:\: By\:\:Step\:\:Explanation}}$

We know that ~

$\huge\boxed{\mathrm{F = \dfrac{ Gm_1m_2}{ r²}}}$

where ~

F = gravitational force

$m_1$ = mass of 1st object = 70 kg

$m_2$ = mass of 2nd object = 2000 kg

G = gravitational constant = $6.674 × {10}^ {-11}$

r = distance between the objects = 1 m

Let's calculate the force ~

$F = \dfrac{6.674 \times 10 {}^{ - 11} \times 70 \times 2000 }{1 {}^{2} }$

$F =6.674 \times 7 \times 2 \times 10 { }^{ - 11} \times 10 {}^{4}$

$93.436 \times 10 {}^{ - 7}$

$9.3436 \times 10 {}^{ - 6} \: \: newtons$

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3 years ago

Estimate the order of magnitude of the length in meters of each of the following: a. a ladybug b. your leg c. your school buildi

sukhopar [10]

The order of the magnitude of the length in meters is estimated based on the average length of the object: if it is a small object then the unit would be cm and if it is a long object (like a road or something) the distance can be measured in km. Then we convert the unit we measured in into the SI unit of the meter.

Based on this, for the mentioned objects, the estimated length would be as follows:
a- ladybug: 10^-2 meters
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d- a giraffe: 10^0 meters
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Scorpion4ik [409]

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<u>Explanation:</u>

To express velocity which is too far from the planet and escape velocity by using the energy conservation, we get

Rock’s initial velocity , $v_{i}=2 v_{e}$ . Here the radius is R, so find the escape velocity as follows,

$\frac{1}{2} m v_{e}^{2}-\frac{G M m}{R}=0$

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From given conditions,

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4 years ago

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Answer and explanation:

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