Answer:
Explanation:
The <em>half-life </em>of a radioisotope, in this case carbon-14, is the time that a sample requires to reduce its amount to half, and it is a constant for every radioisotope (it does not change with the amount of sample).
Then, the formula for the remaining amount of a radioisotope is:
Where:
- A is the final amount of the element,
- A₀ is the initial amount of the element,
- A/A₀ is ratio of remaining amount to the original amount, and
- n is the number of half-lives elapsed
The number of half-lives for carbon-14 elapsed for the dinosaur fossil is:
- n = 68 million years / 5730 years ≈ 11,867
Then, A / A₀ = (1/2)ⁿ = (1/2)¹¹⁸⁶⁷ ≈ 0.00000 .
The number is too small, and when you round to five decimal places the result is zero. That is why carbon-14 cannot be used to date dinosaur fossils, given that they are too old.
I think you're asking what his 'ke' will be. Does that mean his 'kinetic energy' ? Well, that'll just be
<em>ke = (1/2) x (his mass) x (his speed when he touches down)²</em>
Explanation:
It is given that,
Resistance, R = 20 ohms
Voltage of the battery, V = 10 V
We can find current flowing through the circuit using Ohm's law as follows :
V = IR
It can be seen from the Ohm's law, that the current is directly proportional to the voltage. It means that if the battery is replaced by a battery that provides a larger voltage, the current through the circuit will be more than 0.5 A i.e. it increases.
Answer:
Explanation:
According to Newton's third law, every action has an equal and opposite reaction
so it tells us that the force exerted by the earth on the spacecraft is equal to the force exerted by the spacecraft on the earth. But we do not see the earth moving towards the spacecraft because the inertia of the spacecraft is very less than the inertia of the earth.
we know the equation for the period of oscillation in SHM is as follows:
T = 2 * pi * sqrt(mass/k)
we know f = 1/T, so f = 1/(2 * pi) * sqrt(k/m).
since d = v*T, we can say v = d/t = d * f
the final equation, after combining everything, is as follows:
v = d/(2 * pi) * sqrt(k/m)
by plugging everything in
v = .75/(2 * pi) * sqrt((1 * 10^5)/(30))
We find our velocity to be:
v = 6.89 m/s