Question

Minutnaya strelka chasov za odin chas sovershaet polniy oborot. chemu Rovno lineynaya skorost kontsa strelki dlinnoy 5 cm
2)kakovi radiusi krivizni poverkhnost sobiraushey linzi s opticheskoy siloy 5dptr
3) kakoe kolichestvo electrichestva prokhodit cherez poperechnoe secheniye provodnika soprotivleniem 1kOm v techeniye 10s esli na konchakh provodnika podano napryajenie 200v

Answer 1

1) Chtobi naiti lineynuu skorost' nado umnozit uglovuu na dlinu strelki. Uglovaya ravna 2π/3600, znacit lineynaya = 2π/3600*0.05 = 87.2 mkm/sec

2) Po formule dla dvoakovipukloy linzi

$D = 2(n-1)/R\\ R = 2(n-1)/D = 2(1.5-1)/5 = 1/5$ metra

3) Po zakonu Oma I = U/R = 200/1000 = 1/5 A
Zarad raven I*t = 1/5*10 = 2 Kulona