If Fa=4N,W .Fnet=6N,W and has a mass of 3kg. What will be the Fb and Acceleration?

[tinymorning227]

If Fa is 5000N,E
Fnet is 3000N,E
Acceleration is 2m/s^,E

What is the Fb and it's mass?

[Dambarudhar]

1) Fa = 4 N, W.
Fnet = 6 N, W
Acceleration = a
Mass = M = 3 kg
Fnet = Ma
=> 6 N, W = (3 kg)a
=> a = (6 N, W)/(3 kg) = (6/2) m/s², W
Fa + Fb = Fnet
=> Fb = Fnet - Fa
= 6 N, W - 4 N, W
= (6 - 4) N, W = 2 N, W
2) Fa = 5000 N, E
Fnet = 3000 N, E
Fa + Fb = Fnet
=> Fb = Fnet - Fa
Acceleration = a = 2 m/s², E
=> Fb = 3000 N, E - 5000 N, E
= - 2000 N, E
= 2000 N, W
Mass = M
Fnet = Ma
=> M = Fnet / a
=> M = (3000 N), E / (2 m/s²) E
M = *(3000 / 2) kg = 1500 kg