You are riding in the passenger seat of a car as it travels along a straight portion of highway. The car continues traveling at a constant speed as it follows a sharp, unbanked curve to the left. You feel the door pushing on the right side of your body. Can you explain why?.

We feel the door pushing on the right side of our body because we lean suddenly towards the right side when an abrupt turn is taken by the car due to the inertia of our body mass.

Explanation:

Inertia is the property of a body in accordance with the Newton's first law of motion by the virtue of which it continues to be in the state of rest or in uniform motion until acted upon by an external force. Greater the mass of a body, greater is its inertia.

In this case when sitting in a car traveling on a straight path we have a constant velocity. When all of a sudden there is a change in direction then our inertial tendency of moving in a straight linie with a certain velocity is disturbed by the rate of change in momentum which is responsible for the force according to the Newton's second law of motion.

This also happens because our lower part of body is directly in contact with the seat of the car while the upper part is not. So, when there is an abrupt change in the velocity we experience a lag in the weight transfer which is always in the opposite direction of the change in motion.

This effect can be clearly visible when we move along with a half filled bottle of a liquid which will show the effects of transition in a sensitive manner detecting very small changes.