You mean like a box sitting on a table.
One force is the force of gravity, pulling downward on the box.
Now, you know that the forces acting on the box must be balanced, because
if they're not, then the box would be accelerating. But it's just sitting there, so
there must be some other force, just exactly the right strength and direction to
exactly cancel the force of gravity on the box, so that the net force on it is zero.
The other force is the force of the table pushing upward on the box. It's called
the "normal force".
Watchglass is a lab equipment that is used as a cover to prevent heated materials from splattering out of the container and as a holding plate for hot or flammable materials
<u>Explanation:</u>
Watch glass is an equipment used as a cover to prevent heated materials from splattering out of the container and as a holding plate for hot or flammable materials. It is a kind of concave glass which is also used to evaporate a liquid and also provides good air circulation which is used during cooking. The name watchglass was derived as they are see through and so similar to pocket glasses.
<span>Centripetal force acts toward the center of the circle, and inertia keeps the object moving forward.
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The answer would be option D "a ball sitting on a shelf." Potential energy is the amount of energy a object has while it's at rest.. (or not moving) Kinetic energy is how much energy a object is while it's moving. So in this case it's option D because a ball sitting on a shelf isn't moving therefore it has potential energy. It's not option A because thats a example of kinetic energy since how the roller coaster is moving. It's not option B because it's kinetic energy because the bike is moving. It's also not option C because it's kinetic energy because the bird is moving.
Hope this helps!
