Answer:
<u>Option "C":</u> "4.5 g"
Explanation:
N0 = 36 g, Let half-life is T.
t = 3 T, n is number of half lives = t / T = 3
<u>By using the decay law of radioactivity</u>
N / N0 = (1 / 2)^n
where
"N0" be the "initial amount"
"N" be the "amount left"
"n" be the "number of half-lives"
N / 36 = (1/2)^3
N / 36 = 1 / 8
N = 36 / 8 = 4.5 g
Answer:
-589.05 J
Explanation:
Using work-kinetic energy theorem, the work done by friction = kinetic energy change of the base runner
So, W = ΔK
W = 1/2m(v₁² - v₀²) where m = mass of base runner = 72.9 kg, v₀ = initial speed of base runner = 4.02 m/s and v₁ = final speed of base runner = 0 m/s(since he stops as he reaches home base)
So, substituting the values of the variables into the equation, we have
W = 1/2m(v₁² - v₀²)
W = 1/2 × 72.9 kg((0 m/s)² - (4.02 m/s)²)
W = 1/2 × 72.9 kg(0 m²/s² - 16.1604 m²/s²)
W = 1/2 × 72.9 kg(-16.1604 m²/s²)
W = 1/2 × (-1178.09316 kgm²/s²)
W = -589.04658 kgm²/s²
W = -589.047 J
W ≅ -589.05 J
The answer would be 4, each kinetic equation has 4 variables
