Answer:
Probably the more correct version of the story is that Newton, upon observing an apple fall from a tree, began to think along the following lines: The apple is accelerated, since its velocity changes from zero as it is hanging on the tree and moves toward the ground. Thus, by Newton's 2nd Law there must be a force that acts on the apple to cause this acceleration. Let's call this force "gravity", and the associated acceleration the "acceleration due to gravity". Then imagine the apple tree is twice as high. Again, we expect the apple to be accelerated toward the ground, so this suggests that this force that we call gravity reaches to the top of the tallest apple tree.
Answer:
A flower emits only visible light
A flower reflects much of the light that hits it
-- The net vertical force on the object is zero.
Otherwise it would be accelerating up or down.
-- The net horizontal force on the object is zero.
Otherwise it would be accelerating horizontally,
that is, its 'velocity' would not be constant. That
would contradict information given in the question.
The total net force on the object is the resultant of the
net vertical component and net horizontal component.
Total net force = √(0² + 0²)
= √(0 + 0)
= √0
= Zero.
The correct answer is the last choice on the list.
Also, you know what ! ? It doesn't even matter whether the surface it's
sliding on is frictionless or not.
If the object's velocity is constant, then the NET force on it must be zero.
If it's sliding on sandpaper, then something must be pushing it with constant
force, to balance the friction force, and make the net force zero. If the total
net force isn't zero, then the object would have to be accelerating ... either
its speed, or its direction, or both, would have to be changing.