Heat can be transferred from one place to another by three methods:
conduction in solids,
convection of fluids (liquids or gases),
radiation through anything that will allow radiation to pass.
I'm gonna have to assume the girl is on the right side and boy on left.
The net force is the sum of all forces on an object (includes negatives).
Let's say the force of the boy is variable <em>b</em>. Use the formula F = ma.
<em>b </em>+ 3.5 = 0.2(2.5)
This is now simple algebra. Solve to get that <em />the boty is exerting a force of -3N to the left.
Answer:
h = 50.49 m
Explanation:
Data provided:
Speed of skier, u = 2.0 m/s
Maximum safe speed of the skier, v = 30.0 m/s
Mass of the skier, m = 85.0
Total work = 4000 J
Height from the starting gate = h
Now, from the law of conservation of energy
Total energy at the gate = total energy at the time maximum speed is reached

where, g is the acceleration due to the gravity
on substituting the values, we get

or
170 + 833.85 × h = 4000 + 38250
or
h = 50.49 m
The Kelvin scale has no negatives on it.
Zero Kelvin is 'Absolute Zero', and nothing can get colder than that.