Step 1: Understanding the relationship between picks and shaft rotation.
In a shuttle loom, one pick is inserted for every one complete revolution of the bottom shaft. Therefore, the rotational speed of the bottom shaft is equal to the number of picks per minute.
Step 2: Converting picks per minute to revolutions per second.
Given picks per minute = 240
\[
\text{Revolutions per second} = \frac{240}{60} = 4 \text{ rps}
\]
Step 3: Converting revolutions per second to angular velocity.
Angular velocity $\omega$ is given by:
\[
\omega = 2\pi \times \text{rps}
\]
\[
\omega = 2\pi \times 4 = 8\pi \text{ rad/s}
\]
Step 4: Identifying the value of $n$.
Comparing with $\omega = n\pi$, we get:
\[
n = 8
\]
Step 5: Conclusion.
Hence, the value of $n$ is 8.