I believe the answer is valcanos because they release sulfur in to the air and other chemicals so it willl affect the anispher
An earthworm moves by using two different sets of muscles. 2. FISHES :- Fish swim by flexing their bodies and tail back and forth. Fish stretch or expand their muscles on one side of their body, while relaxing the muscles on the other side.
First you need to make a difference between friction while object is stationary and the friction while object is moving. Force required to start moving some object is slightly greater than force required to maintain objects movement. That means that to move a chair you need some force F1 but you can than slightly reduce force and chair will still be moving.
Now to the problem in this question: It can be said that "stationary friction force" is equal to 15 Newtons. Its also good to know that friction force between chair and floor while you are increasing your push is also increasing and is equal to force of your push. Once it reaches 15N which is it "critical value" for that chair, chair starts moving and friction force drops a little bit and now it is called friction force of moving chair.
From the equation, r is the distance from the center of the tube. When r = 0, you're considered to be at the centerline and the expression has the highest value. Therefore, the velocity of a viscous fluid is greatest at the center of the tube.
