Answer:
1694 days
Explanation:
In first-order kinetics, the rate is proportional to the amount.
dA/dt = kA
For first-order kinetics, the rate k can be found using the half-life:
t₁,₂ = (ln 2) / k
In other words, the half-life is inversely proportional with the rate.
At the lower temperature, the rate is reduced to a third, so the half-life increases by a factor of 3. Meaning that the new half-life is 170 × 3 = 510 days.
The "shelf life" is the time it takes to reduce the initial amount to 10%. We can solve for this using the half-life equation.
A = A₀ (½)^(t / t₁,₂)
A₀/10 = A₀ (½)^(t / 510)
1/10 = (½)^(t / 510)
ln(1/10) = (t / 510) ln(½)
ln(10) = (t / 510) ln(2)
ln(10) / ln(2) = t / 510
t = 510 ln(10) / ln(2)
t ≈ 1694
Answer:
I don't really know this one sorry
Answer:
A. 91 meters north
Explanation:
Take +y to be north.
Given:
v₀ = 13 m/s
a = 0 m/s²
t = 7 s
Find: Δy
Δy = v₀ t + ½ at²
Δy = (13 m/s) (7 s) + ½ (0 m/s²) (7 s)²
Δy = 91 m
The displacement is 91 m north.
