Answer:
F = 47.6 N
Explanation:
- Newton's 2nd law can be expressed as the rate of change of the total momentum, respect of time, as follows:
- So, in order to find the average force exerted by the skater on the wall, we can find the change in momentum due to the force exerted by the wall (which is equal and opposite to the one exerted by the skater), and divide it by the time interval , as follows:
⇒ Fsk = 47.6 N (normal to the wall)
It might be radiation and reflection but I’m not sure
Answer: 1.95
Explanation:
You should start off from the decay formula and solve for τ:
Apply inverse logarithmic function:
The final form will be:
Inputing values for I, IO, and t:
Answer:
1.85 J/K
Explanation:
The computation of total change in entropy is shown below:-
Change in Entropy = Sum Q ÷ T
= 
= -3.12 + 4.97
= 1.85 J/K
Therefore for computing the total change in entropy we simply applied the above formula.
As we can see that there is heat entering the reservoir so it will be negative while cold reservoir will be positive else the process would be impossible.
Answer:
She does a work of 689.44 J in the snow.
Explanation:
A force is said to do work when it alters the state of motion of a body. The work of the force on that body will be equivalent to the energy needed to move it.
In other words, Work is a form of energy transmission between bodies. In order to carry out work, a force must be exerted on a body and it must move.
The work is equal to the product of the force times the distance and the cosine of the angle that exists between the direction of the force and the direction that the moving point or object travels:
W= F*d* cos Ф
Work W is measured in joules (J), force is measured in newtons (N), and displacement in meters (m).
In this case:
- F= 180 N
- d=5 m
- Ф= 40 degrees
Replacing:
W= 180 N*5 m* cos 40
Solving:
W= 689.44 J
<u><em>She does a work of 689.44 J in the snow.</em></u>
