Respostas

2013-08-23T17:30:31-03:00
Letra a)

Temos que:

Força resultante (Fr)

Fr² = F1² + F2² + 2 * F1*F2 * cos(alpha)

Fr² = 1² + V2² + 2*1*V2 * V2/2

Fr² = 1 + 2 + 2*V2² / 2

Fr² = 3 + 2

Fr² = 5

*********************************
Fr =  \sqrt{5} N
*********************************


Letra B)

Fr² = F1² + F2² + 2*F1*F2*cos(alpha)

Fr² = V2² + V2² + 2*V2*V2 * cos(90°)

Fr² = 2 + 2 + 2V2² * 0

Fr² = 2 + 2

Fr² = 4

Fr =  \sqrt{4}

***********
Fr = 2N
***********