Answer: 9 days
Explanation:
- Step 1
Let the rate of Leaf growth <em>r</em> be defined as, =
where <em>A</em> is initial area of the leaf, <em>A1</em> is the final area of the leaf and<em> t</em> is the time taken for the increase in Area.
- Express the proportional relationship in equation.
Given that rate of leaf growth, r is proportional to the surface area of the leaf A. we have r ∝ A.
r = kA, where k is the rate constant.
therefore, k =
when A = 2, A1 = 3
so k =
= ÷ 2
= 0.33 ÷ 2
k = 0.167
- After calculating the rate constant k, we then find the time t when A1 is 5
- we have r = k × A1 =
so, 0.167 × 2 =
0.33 = .
t = 3/0.33
Therefore, t = 9 days.