Question

VA ROG !!! am nevoie sa rezolvati exercitiile 18, 19, 21, 22, 23, 24, 27, 28, 29, 30 de pe fisa de mai sus !!!

Answer 1

17)

Pentru Logan: 

$\it v=\dfrac{d}{t} \Rightarrow 50=\dfrac{100}{t} \Rightarrow t=2h$

Pentru Sandero :

$\it v=\dfrac{d}{t} \Rightarrow 40=\dfrac{d}{2} \Rightarrow d = 40\cdot2 \Rightarrow d = 80 \ km$


20)

[tex]\it v = 40cm/s,\ \ \ d = 70m=7000cm \\\;\\ v = \dfrac{d}{t} \Rightarrow 40 = \dfrac{7000}{t} \Rightarrow 40\cdot t = 7000 \Rightarrow t = 7000:40 =175\ s[/tex]

27)

 $\it \rho =\dfrac{m}{V} \Rightarrow m = \rho\cdot V = 50\cdot900 = 45000\ kg = 45\ t$