Explanation:
When a car is at rest, all the passengers inside the car are also at rest. According to Newton's first law of motion, an object at rest will stay at rest unless acted upon by an external force. Therefore, the passengers in the car experience a state of rest known as inertia of rest.

However, when the car suddenly starts moving, an external force is applied to the car, causing it to accelerate. This acceleration is also experienced by the passengers inside the car. Due to their inertia of rest, the passengers tend to remain at rest while the car accelerates forward. As a result, the passengers feel a jerk or a sudden backward push.

Key Points:
- Passengers sitting in a stationary car experience a jerk when the car suddenly starts moving.
- This is due to the inertia of rest.
- Inertia of rest is a property of matter that resists any change in its state of rest.
- According to Newton's first law of motion, an object at rest will stay at rest unless acted upon by an external force.
- When the car accelerates, an external force is applied to the car, causing it to move forward.
- The passengers inside the car tend to remain at rest due to their inertia of rest.
- As a result, they feel a jerk or a sudden backward push.
- This jerk is a result of the conflict between the car's acceleration and the passengers' tendency to remain at rest.
- Once the car starts moving, the passengers experience the inertia of motion instead of the inertia of rest. This means they will continue to move forward with the same speed and direction as the car, unless acted upon by another external force.
- Inertia of turning and inertia of acceleration are not relevant in this scenario. Inertia of turning refers to the resistance to a change in the direction of motion, while inertia of acceleration refers to the resistance to a change in the rate of motion.