Both of those courses had minimal workload :'D. It was just four tests and the exam for 1LS3 when I took it in 2010. Physics only has one midterm, but there are tutorials with quizzes in them. It's not hard to do well in those if you have a decent math/physics background.
You will probably need to take physics 1b03 later on in upper years, though, so just keep that in the back of your mind
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