An object whose mass is $m$ is crashing into the ground and leaping with the same velocity. If the duration of the interaction between the object and the ground is $0.1$ seconds, determine the force ground applied to the object.
I know that
$$\Delta P_y = F_y \times \Delta t$$
$$\Delta P_y = (N-mg) \times \Delta t$$
$$2mv_0 \sin \theta = (N-mg) \times \Delta t$$
Hence we get
$$N = 220N$$
According to answer key, it seems incorrect.