91影视

How can we tell whether a body is exerting a force on another body?

Can an object have force? Can an object exert a force? Can an object be a force? Can an object feel a force?

List at least six specific examples of forces. Try to list examples that are significantly different.

What is a resistive force? Give two examples.

Give two examples of forces that act at a distance.

What do we mean when we say that one object has 鈥渕ore inertia鈥� than another object?

When you move an object from Earth to the moon, does its inertia change? Does its weight change? Does its mass change? Does its amount of matter change? Does its acceleration differ while falling freely? Does it respond differently to a net force of 1N?

Forces of 8 N and 3 N act on an object. How strong is the net force if the two forces have opposite directions? The same directions?

Is an object鈥檚 acceleration always in the same direction as its velocity (its direction of motion)? If not, give an example in which it is not. Is an object鈥檚 acceleration always in the same direction as the net force on the object? If not, give an example in which it is not.

As you increase the net force on an object, what happens to its acceleration? What if you double the net force? As you increase the mass of an object (for example, by gluing additional matter to it), what happens to its acceleration? What if you double the mass?