The complete question is;
James Joule (after whom the unit of energy is named) claimed that the water at the bottom of Niagara Falls should be warmer than the water at the top, 51 m above the bottom. He reasoned that the falling water would transform its gravitational potential energy at the top into thermal energy at the bottom, where turbulence brings the water almost to a halt. If this transformation is the only process occurring, how much warmer will the water at the bottom be?
Answer:
Water becomes warmer by a temperature of ΔT = 0.119 K
Explanation:
If we assume that gravitational kinetic energy will be converyrf into thermal enrgy, we will have;
Q = U
So, m•c_w•ΔT = mgh
Where;
c_w is specific heat capacity of water with a value of 4184 J/Kg.K
ΔT is change in temperature indicating how warmer the water will be. Thus making ΔT the subject, we have;
ΔT = gh/c_w
So, ΔT = 9.8 x 51/4184 = 0.119 K
Answer:
10.87 m
Explanation:
Total length of the wire = 25 m
Let the length of one piece is y and other piece is 25 - y
Let the side of square is a.
So, 4 a = y
a = y / 4
And the side of triangle is b
3 b = (25 - y)
b = (25 - y) / 3
Area of square, A1 = side x side =
A1 = y² / 16
Area of equilateral triangle, A2 =
Total area, A = A1 + A2
For maxima and minima, fins dA /dy
It is equal to zero.
9y = 173.2 -6.928 y
15.928 y = 173.2
y = 10.87 m
So, the length of wire to make square is 10.87 m.
Answer:Friction force
Explanation:
The frictional force is responsible for stopping the moving object.
The friction force is provided by nature in the form of air resistance, fluid resistance, Surface resistance.
For surface resistance, the friction force is of two types namely kinetic friction force and static friction force.
Static friction acts when the object is stationary and a force is applied to cause the motion while kinetic friction acts when the body starts moving.
kinetic friction is lesser is in magnitude as compared to static friction.
Skin is a huge on. there is also tears and mucous membranes