Everyday we take part in physics whether we like it or not. Walking is a perfect example. When we walk, we push the ground backwards, and the ground pushes us forwards with accordance to newton's 3rd law. In fact we walk on due to the presence of frictional force. We do work against friction to walk. Also when you sit you still are involved in physics. While sitting you are applying a force ion whatever object you are sitting on. This force is called MG which is the (total mass)(gravity). So in order to even that force out, the ground forces an equal force back in the opposite direction of the initial force. This causes you to stay still until you are acted upon by a force. This is a result of newton's 3rd law also.