The practice of science can answer only scientific questions. And scientific questions guide the design of investigations. What must be true of the
possible answers to a scientific question?
A. They support an established scientific theory.
B. They do not require the use of physical measurements.
C. They could be shown to be false by evidence.
D. They are at odds with established scientific theories.

Aperson stands on a platform, initially at rest, that can rotate freely without friction. the moment of inertia of the person plus the platform is ip. the person holds a spinning bicycle wheel with its axis horizontal. the wheel has moment of inertia iw and angular velocity ωw. take the ωw direction counterclockwise when viewed from above. part a what will be the angular velocity ωp of the platform if the person moves the axis of the wheel so that it points vertically upward?

Aperson walks first at a constant speed of 4.89 m/s along a straight line from point a to point b and then back along the line from b to a at a constant speed of 2.95 m/s. what is the average speed over the entire trip?

What is the force that opposes motion and works against the downward pull? a) friction b) gravity c) weight d) acceleration