Question

Calculati energia cinetica a corpului cu 39 kg atunci cand:
A-mergeti la pas v=4km/h
B-alergati v=10km/h

Urgent
Ma verifaca la tema asta

Answer 1

Energia cinetica = masa x viteza ² / 2 

masa = 39 kg 

1) viteza "la pas" = 4 km/h = 4000 m / 3600 s = 1,111 m/s 

     Ec = 39 kg x (1,11 m/s)² / 2 = 24, 07 kg m² / s² = 24,07 jouli 

2) viteza in alergare = 10 km/h = 10000  m / 3600 s = 2,777 m/s 

      Ec = 39 kg x (2,777m/s)² / 2 = 150,46 kg m²/s² = 150,46 Jouli