Answer:
7800 J
Explanation:
Heat needed = mass of copper x specific heat of copper x change in temperature
Change in temperature = 30ºC - 20ºC = 10ºC
Specific heat of copper = 390 J/kgºC
Mass of copper = 2 Kg
Substituting the given values in above equation, we get –
Heat needed = 2 Kg x 390 J/kgºC x 10ºC
= 7800 J
Answer:
Explanation:
F = ma
<u>Assuming</u> the 20° is angle θ measured to the horizontal
mgsinθ - μmgcosθ = ma
g(sinθ - μcosθ) = a
at constant velocity, a = 0
g(sinθ - μcosθ) = 0
sinθ - μcosθ = 0
sinθ = μcosθ
μ = sinθ/cosθ
μ = tanθ
μ = tan20
μ = 0.3639702342...
μ = 0.36
To solve this problem we will apply the concepts of equilibrium and Newton's second law.
According to the description given, it is under constant ascending acceleration, and the balance of the forces corresponding to the tension of the rope and the weight of the elevator must be equal to said acceleration. So


Here,
T = Tension
m = Mass
g = Gravitational Acceleration
a = Acceleration (upward)
Rearranging to find T,



Therefore the tension force in the cable is 10290.15N
Can I see the graph so I can help you
Answer:
Coefficient of friction.
Explanation:
The amount of friction divided by the weight of an object is equal to the coefficient of friction. It is a dimensional less number. It can be given by :

N is normal force.
= coefficient of friction
