A 2 kg mass accelerates at 5.7 m/s
2
in a
direction 19◦
north of east. One of the two
forces acting on the mass has a magnitude of
17.1 N and is directed north.
Determine the magnitude of the second
force.
Answer in units of N
a = 5.7m/s^2[19o]
m = 2kg
F1 = 17.1N[90o] = 17.1i
F2 = ?
Fn = m * a = 2 * 5.7[19o] = 11.4N.[19o]=
10.78 + 3.71i.
F1 + F2 = Fn = 10.78 + 3.71i
17i + F2 = 10.78 + 3.71i
F2=10.78 + 3.71i - 17.1i=10.78 -13.39i
F2^2 = 10.78^2 + 13.39^2 = 295.5
F2 = 17.2 N