Answer: Newton's First Law states that an object at rest will stay at rest, and an object in motion will stay in motion at the same speed and direction, unless acted upon by an unbalanced force. This is also called the Law of Inertia. For example, a ball will keep rolling until friction or something else stops it.

Answer: The formula is F = ma, where F = force (measured in Newtons), m = mass (measured in kilograms), and a = acceleration (measured in meters per second squared). This means force equals mass times acceleration.

Answer: When you jump, you push down on the ground (action force) and the ground pushes up on you with equal force (reaction force). The forces are equal in strength but opposite in direction. Other examples include swimming (pushing water backward to move forward) or rockets (pushing gas down to go up).

Answer: According to Newton's Second Law (F = ma), if you want the same acceleration (a) but the mass (m) is larger, then the force (F) must be larger too. Heavier objects have more inertia, which means they resist changes in motion more than lighter objects.

Answer: When a car suddenly stops, Newton's First Law explains that passengers will continue moving forward at the same speed the car was traveling because of inertia. Seatbelts provide the unbalanced force needed to stop the passengers' motion and keep them safe in their seats.

Answer: Rockets work using Newton's Third Law. They don't need air to push against. Instead, they burn fuel and shoot hot gases out the back (action force). The equal and opposite reaction force pushes the rocket forward. This works even better in space because there's no air resistance to slow the rocket down.

Answer: This demonstrates Newton's Second Law (F = ma). A full shopping cart has more mass than an empty one. To accelerate both carts at the same rate, you need to apply more force to the heavier cart. Since you're applying the same force to both, the empty cart (less mass) will accelerate more easily than the full cart (more mass).