TBR Physics Work on a Block question

[pineapplemangofarmer]

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I just want to clarify something for two questions in this passage: #43 and #48.

The only reason the lifter does more work in II and III for problem #48 is because friction is present right?

For #43, the work done is the same because we are not accounting for friction?

 

[suckerpin]

yep; the change in PE is the work done, on the last line of the passage its says to ignore friction. Since the boxes end up at the same height (h) the same amount of work is done for all three