Description
The instant variation of the contents of a minecart hopper on a detector rail, will produce a change in the redstone signal after an unusualy long delay.

Example
When you put something in an empty minecart hopper on a detector rail, the comparator will detect this change with a delay greater than 1 redstone tic.

In comparaison, when you put something in an empty hopper, the comparator will detect this change instantly and 1 redstone tic later, the comparator will ouput a True signal.

By the simple test in the attachment, we can hear with the note block that the delay of detection of change in the minecart hopper is substantially slower than the hopper.

Why this is important

• This inconsistency affects redstone contraption by addind delay.
• This Delay affects the accuracy of controls of automatic minecart contraption
• This inconsistency can confuse new player learning redstone

Thanks for the support.