Answer:
Explanation:
Lead has an half life of 43.5 seconds
The radioactive decay law says
N(t) = No•2^(-t / t½)
Hence, the percent of a sample of the Lead-214 isotope that decay after a time equivalent to 7 half-lives
N(t) = No•2^(-t / t½)
N(t) / No = 2^(-t / t½)
N(t) / No = 2^-7
N(t) / No = 7.81 × 10^-3
To percentage
N(t) / No = 7.81 × 10^-3 × 100
N(t) / No = 0.781 %
Answer: A man known as H.M suffered from <u>epileptic seizures </u>after an operation removed portions of his <u>memory</u>.
.
Explanation:
Answer:
a = 5.65 m/s² (↑)
Explanation:
T = 34.012 N (↑)
m = 2.2 Kg
g = 9.81 m/s²
We apply Newton's 2nd Law as follows:
∑ Fy = m*a
⇒ T - W = m*a
⇒ T - m*g = m*a
⇒ a = (T - m*g) / m
Finally
⇒ a = (34.012 N - 2.2 Kg*9.81 m/s²) / 2.2 Kg
⇒ a = 5.65 m/s² (↑)
Wind turbines work on a simple principle: instead of using electricity to make wind—like a fan—wind turbines use wind to make electricity. Wind turns the propeller-like blades of a turbine around a rotor, which spins a generator, which creates electricity.