Question Number 23481 by Tinkutara last updated on 31/Oct/17
$$\mathrm{Which}\:\mathrm{of}\:\mathrm{the}\:\mathrm{diagrams}\:\mathrm{represents} \\ $$$$\mathrm{variation}\:\mathrm{of}\:\mathrm{total}\:\mathrm{mechanical}\:\mathrm{energy}\:\mathrm{of} \\ $$$$\mathrm{a}\:\mathrm{pendulum}\:\mathrm{oscillating}\:\mathrm{in}\:\mathrm{air}\:\mathrm{as}\:\mathrm{function} \\ $$$$\mathrm{of}\:\mathrm{time}? \\ $$
Commented by Tinkutara last updated on 01/Nov/17
$$\mathrm{Thank}\:\mathrm{you}\:\mathrm{very}\:\mathrm{much}\:\mathrm{Sir}! \\ $$
Commented by Tinkutara last updated on 31/Oct/17
Commented by ajfour last updated on 31/Oct/17
$$\left({c}\right)\:{air}\:{resistance}\:{proportional} \\ $$$${to}\:{speed}.{There}\:{might}\:{also}\:{be} \\ $$$${interference}\:{fringes}\:{within} \\ $$$${the}\:{decaying}\:{diffraction}\:{pattern}. \\ $$$$\:\left(:\:!\right) \\ $$
Commented by Tinkutara last updated on 31/Oct/17
$$\mathrm{Why}\:\mathrm{does}\:\mathrm{not}\:\left({b}\right)?\:\mathrm{Why}\:\mathrm{M}.\mathrm{E}.\:\mathrm{is}\:\mathrm{never}\:\mathrm{0}? \\ $$
Commented by ajfour last updated on 31/Oct/17
$${when}\:{amplitude},\:{hence}\:{speed} \\ $$$${decreaese}\:{and}\:{becomes}\:{small} \\ $$$${the}\:{rate}\:{of}\:{losz}\:{in}\:{mechanical}\:{energy} \\ $$$${becomes}\:{small}\:{too}.. \\ $$