Answer:
v = 9.04 m / s
Explanation:
For this exercise we can use the relation that the work of the non-conservative force (friction) is equal to the variation of the mechanical energy of the system.
W = Em_f - Em₀ (1)
Starting point. Lower slope
Em₀ = K = ½ m v²
highest point. Where is the skier at a height h
Em_f = U = m g h
The work of rubbing
W = -fr x
the negative sign is because the friction force opposes the movement.
Let's set a reference system where the x axis is parallel to the slope and the y axis is perpendicular
let's use trigonometry to break down the weight
cos θ = W_y / W
sin θ = Wₓ / W
W_y = W cos θ
Wₓ = W sin θ
Y axis
N - Wₓ = 0
N = mg sin θ
X axis
fr = m a
the friction force has the expression
fr = μ N
fr = μ mg sin θ
we look for the job
W = - μ mg sin θ x
where x is the distance along the slope
we substitute in 1
-μ mg sin θ x = mg h - ½ m v²
let's use trigonometry to find the distance x
tan 30 = h / x
x = h / tan 30
we substitute
- 
= m gh - ½ m v²
we use
tan 30 = sin30 / cos30
v² = 2g h + 2 μ g h cos 30
v = 
let's calculate
v = 
v = 9.04 m / s
There are different kinds of conductors, most notably electrical and thermal conductors. But they are often inclusive of each other (electrical conductors are typically good thermal conductors).
A conductor transmits something through its body with high efficiency while an insulator does not transmit very well. In the case of electricity, a conductor transmits electrical energy between two points while an insulator blocks the flow of electricity.
Two examples of conductors are copper and silver. Two examples of insulators are wood and styrofoam.
Answer:
4276.98 years
Explanation:
t = age of the sample in numbers of years
T = half life of the carbon-14 isotope = 5730 yrs
λ = decay constant of carbon-14
decay constant is given as
A₀ = activity of Carbon-14 in living plants
A = activity of Carbon-14 after time "t" = (0.596) A₀
Using the equation
t = 4276.98 years
Answer:
conductivity of solution is reduced.
Explanation:
When two oppositely charged electrodes are immersed in a solution, positively charged ions are attracted to the negative electrode and gain electrons. The negatively charged ions are attracted to the positive electrode and release electrons.
Due to the process mentioned above , the negatively charged ions are accumulated at the positive electrode and the positively charged ions are accumulated at the negative electrode . This accumulation prevents further attraction of ions at oppositely charged electrodes because the incoming ions face repulsion from already accumulated ions at electrodes. Further , it creates an emf acting in opposite direction . It reduces the current through the solution. Hence conductivity of solution is reduced.
