Question

A 9 kg block is attached to a spring on the side of a wall. The spring is compressed 15 cm and let go. The force of the spring acts on the block in the positive x-direction and the force of gravity acts on the block in the negative y-direction. If the spring constant of the spring is 240 N/m, what is the magnitude of the net force on the block?

Answer 1

$F_e=k\Delta x=240\cdot0.15=36(N)$

$F_g=mg=9\cdot9.8=88.2(N)$

$F_{net}=\sqrt{F_e^2+F_g^2}=\sqrt{36^2+88.2^2}=95.3(N)$