This
semester has been quite different because of the situation in Latvia. When the
lockdown started, we decided, instead of the regular video lectures, to post a
difficult physics problem for students to solve. This has resulted in two
interesting physics problems.

The first
one was about Tarzan. The question asked, how could Tarzan swing from one vine
to another with a starting velocity v, and whether the velocity would be large enough to get to the
other vine and at what angle should he release from the first vine to catch the
other.

The second problem
was about a magnet system. One magnet was attached to a spring and the other
one was able to freely move. The question was: what is the distance between the
magnets such that the magnet attached to the spring slips and sticks to the
other magnet. And the result of this was used to experimentally measure the
magnetic moment of the magnet.

These problems
posed difficulties to not only the students but also physics professionals. But
quite a few students submitted correct solutions and the fastest correct
submissions were awarded with a popular-science book.

To more challenging
and interesting physics problems next semester.