1) The purse falls to the ground because of Newton’s first law, an object in motion stays in motion and an object at rest will stay at rest until an unbalanced force changes it. The first law includes inertia, which occurs when the object wants to continue to go forwards even when it’s been stopped. When Jane stops her car, the purse wants to keep going forward, therefore falling to the ground.
2) when you’re standing on the board, the board pushes up on you, while you/gravity is pushing downwards // when you jump down, the opposite force pushes upwards, allowing you to go up (jump)
Depending the height your jumping from, if you were jumping from a high structure it's best if you jump and land on knees so you dont sprang your ankles from jumping and landing on your straight legs, you could even pull a muscle if you land on straight legs.
