Question

Chłopiec wchodzi na szczyt wylaczonych ruchomych schodow w ciagu 90 sec.Stojac natomiast na jadacych schodach zostaje przeniesiony w ciagu 60sec. Jak dlugo wchodzilby po schodach jadacych? Prosze o dokladne obliczenia ;)

Answer 1

t1 = 90 s

t2 = 60s

V1 = ?

V2 = ?

S = const

S = v *t

V1 * t1 = V2*t2

V1 * 90s = V2 * 60 s

90V1 = 60 V2

3V1 = 2V2

V1 = (2/3) V2

V2 + (2/3) V2 = (5/3) V2

 

60 s * V2 = t3 * 5/3V2

60s = t3 * 5/3

t3 = 60s/ (5/3)

t3 = 60s * 3/5

t3 = 36s

 

Odp: 36s