Newton's First Law states that an object in motion stays in motion unless acted upon by an external force. Sliding a puck demonstrates this as it continues moving until friction (external force) stops it.

Newton's First Law states that objects in motion continue in motion with constant velocity unless acted upon by a net external force. The student's statement is incorrect because it suggests motion requires a continuous force.

This is the direct statement of Newton's First Law. All objects have inertia (resistance to change in motion), and they only change their motion when acted upon by an external force.

This demonstrates inertia - the tendency of objects to resist changes in their state of motion. The rider's lower body moves with the horse while the upper body tends to stay at rest initially.

This is another example of inertia. The passengers' bodies tend to continue moving forward (their previous state of motion) while the train (and seats) stop suddenly.

Inertia is the property that resists changes to both states of rest and uniform motion. Mathematically, this is expressed as \( \sum \vec{F} = 0 \Rightarrow \vec{a} = 0 \).

According to Newton's First Law, the puck would continue moving indefinitely without friction. The stopping is caused by the frictional force opposing the motion \( F_{\text{friction}} = \mu N \).

The passenger's body tends to continue moving forward (its initial state of motion) due to inertia when the car stops suddenly.

Newton's First Law states that an object at rest remains at rest unless acted upon by an external force. With no kick (external force), the ball remains stationary.

The man's body was in motion with the bus. When his feet stop on the ground, his upper body continues moving forward due to inertia, causing him to fall forward.

Both the apple and the brother have the same horizontal velocity (the train's velocity) when the apple is dropped. According to Newton's First Law, they continue with this velocity, so the apple falls straight down relative to the brother.

Newton's First Law is often called the Law of Inertia, describing how objects resist changes to their state of motion.

This demonstrates how an object in motion (the bicycle) changes its motion only when acted upon by an external force (the brakes).

The gravitational force \( F_g = mg \) is balanced by the normal force \( N \) from the table, resulting in no net force \( \sum F = 0 \), so the book remains at rest.

Both the ball and the car have the same horizontal velocity. When thrown vertically, the ball maintains this horizontal velocity (no air resistance assumed), so it lands back in the thrower's hand.

The total weight remains the same (3 kg) whether the bird is flying or at rest inside the closed cage, as the forces are internal to the system.

According to Newton's First Law, no force is needed to maintain constant velocity \( \vec{v} \). Force \( \vec{F} \) is only needed to change the velocity (accelerate).

An unbalanced (net) force is required to change an object's state of motion. Balanced forces result in no change (constant velocity or rest).

Passengers tend to continue moving straight (their initial motion) due to inertia while the bus turns, making them feel thrown outward.

Newton's First Law is commonly called the Law of Inertia, describing how objects resist changes to their motion.