Answer:
B . unequal heating of the Earth's surface by the sun
Energy cannot be created nor be destroyed
Answer:
the wagon should be used as frame of reference if an observer said the child was not moving.
Explanation:
The state of motion of a body depends upon the frame of reference. It is the set of co-ordinates according to which the motion is analyzed. If a child is riding in a wagon, then he will be considered in motion to a person standing outside the wagon. Hence, if we take a frame of reference outside the wagon then the child must be in motion with respect to the observer. On the other hand if the observer is inside the wagon, then the child must be in rest with respect to the observer. Hence, if we take the wagon to be the frame of reference, then the child will be at rest with respect to the observer.
<u>Therefore, the wagon should be used as frame of reference if an observer said the child was not moving.</u>
Answer:
"Man's mind is far too advanced for his survival needs."
See also "Wallace", Darwin's junior partner who couldn't explain the gap in intelligence.
To solve the problem we apply the motion kinematic equations as well as the techniques used to solve second order polynomial equations.
By definition we know that the height of a body is given by the function
As there is no initial speed or a distance previously traveled, the equation is:
Where,
g = Gravitational acceleration
t = time
h= Height
Rearranging to find the time we have,
Then, the sound of the splash take a time 
to travel back, therefore, in time, it is necessary to adhere the new term, which converts the final time into:
If we make a similarity to the polynomial equation of the second degree where 
we have to:
Solving to find x (which is equivalent to 
) we have to:
Since the positive distance is what allows us to find the actual distance traveled we have finally to
The correct answer is B.
