1. Determine the Visible Height of Each Pillar:
2. Calculate the Buried Height of Each Pillar:
Since each pillar has a total height of 10 units, subtract the visible height from 10 to find the buried height:
3. Calculate the Total Visible Height:
7 + 5 + 3 + 6 + 9 = 30 units
4. Calculate the Total Buried Height:
3 + 5 + 7 + 4 + 1 = 20 units
5. Determine the Ratio:
The ratio of the total volume above the ground to the total volume below the ground is the same as the ratio of their heights because they have equal cross sections.
This ratio is 30:20, which simplifies to 3:2.
Therefore, the ratio of the total volume of the pillars above and below the ground is 3:2.
Let $ a_0, a_1, ..., a_{23} $ be real numbers such that $$ \left(1 + \frac{2}{5}x \right)^{23} = \sum_{i=0}^{23} a_i x^i $$ for every real number $ x $. Let $ a_r $ be the largest among the numbers $ a_j $ for $ 0 \leq j \leq 23 $. Then the value of $ r $ is ________.
Let $ y(x) $ be the solution of the differential equation $$ x^2 \frac{dy}{dx} + xy = x^2 + y^2, \quad x > \frac{1}{e}, $$ satisfying $ y(1) = 0 $. Then the value of $ 2 \cdot \frac{(y(e))^2}{y(e^2)} $ is ________.
The left and right compartments of a thermally isolated container of length $L$ are separated by a thermally conducting, movable piston of area $A$. The left and right compartments are filled with $\frac{3}{2}$ and 1 moles of an ideal gas, respectively. In the left compartment the piston is attached by a spring with spring constant $k$ and natural length $\frac{2L}{5}$. In thermodynamic equilibrium, the piston is at a distance $\frac{L}{2}$ from the left and right edges of the container as shown in the figure. Under the above conditions, if the pressure in the right compartment is $P = \frac{kL}{A} \alpha$, then the value of $\alpha$ is ____