Question

Think about the helical coil of a telephone cord or a spiral binding. Suppose that you view the spiral from one end and find that it is a left-handed twist. If you view the same spiral from the other end, is it a right-handed or left- handed twist?

Short answer

Answer: The orientation of a helical coil remains the same when viewed from both ends. If it has a left-handed twist from one end, it will have a left-handed twist from the other end as well.

Step-by-step solution

Visualize the helix and the orientation when viewed from one end

Observe the telephone cord or the spiral binding and notice the twist of the helix from one end. Let's say it's a left-handed twist initially.

Imagine the view from the opposite end

Now, imagine observing the helix from the other end. Keep in mind, the overall coil orientation will remain the same since a helix has a continuous direction.

Determine the orientation when viewed from the opposite end

As we view the helix from the opposite end, the orientation will still be the same as the initial observation, which is a left-handed twist. The helix maintains its continuous direction throughout and does not change orientation when viewed from different ends. In conclusion, if the helix has a left-handed twist when viewed from one end, it will have a left-handed twist when viewed from the other end as well.