Question

video 2: newton’s 1st law of motion
notes:

1. constant force must be applied to maintain motion against what two things?
2. what is the definition of inertia?
3. more mass means more __________ is needed to start or stop a moving object.

video 3: newton’s 3rd law of motion
notes:

1. how is newton’s 3rd law of motion most famously stated?
2. when a rock falls to the ground, what causes it to accelerate towards the earth?

Explanation:

Video 2: Newton’s 1st Law of Motion Notes

1.

Step1: Recall Newton's 1st Law context

Newton’s 1st Law (Law of Inertia) involves forces opposing motion. The two main resistive factors are friction (opposes motion between surfaces) and air resistance (drag, opposes motion through air).

Inertia is defined as the tendency of an object to resist changes in its state of motion (or rest). An object at rest stays at rest, and an object in motion stays in motion with constant velocity (unless acted upon by a net external force).

Step1: Relate mass to inertia/force

Newton’s 2nd Law ($F = ma$) shows force ($F$) is proportional to mass ($m$) for acceleration ($a$). More mass means more inertia, so more force is needed to change its motion (start/stop it).

Answer:

Friction and air resistance

2.