Answer:
1.503 J
Explanation:
Work done in stretching a spring = 1/2ke²
W = 1/2ke²........................... Equation 1
Where W = work done, k = spring constant, e = extension.
Given: k = 26 N/m, e = (0.22+0.12), = 0.34 m.
Substitute into equation 1
W = 1/2(26)(0.34²)
W = 13(0.1156)
W = 1.503 J.
Hence the work done to stretch it an additional 0.12 m = 1.503 J
Answer:
27 blocks
Explanation:
First, the expression to use here is the following:
P = F/A
Where:
P: pressure
F: Force exerted
A: Area of the block.
Now , we need to know the number of blocks needed to exert a pressure that equals at least 2 atm. To know this, we should rewrite the equation. We know that certain number of blocks, with the same weight and dimensions are putting one after one over the first block, so we can say that:
P = W/A
P = n * W1 / A
n would be the number of blocks, and W1 the weight of the block.We have all the data, and we need to calculate the area of the block which is:
A = 0.2 * 0.1 = 0.02 m²
Solving now for n:
n = P * A / W1
The pressure has to be expressed in N/m²
P = 2 atm * 1.01x10^5 N/m² atm = 2.02x10^5 N/m²
Finally, replacing all data we have:
n = 2.02x10^5 * 0.02 / 150
n = 26.93
We can round this result to 27. So the minimum number of blocks is 27.
