Answer:
T=280.41 °C
Explanation:
Given that
At T= 24°C Resistance =Ro
Lets take at temperature T resistance is 2Ro
We know that resistance R given as
R= Ro(1+αΔT)
R-Ro=Ro αΔT
For copper wire
α(coefficient of Resistance) = 3.9 x 10⁻³ /°C
Given that at temperature T
R= 2Ro
Now by putting the values
R-Ro=Ro αΔT
2Ro-Ro=Ro αΔT
1 = αΔT
1 = 3.9 x 10⁻³ x ΔT
ΔT = 256.41 °C
T- 24 = 256.41 °C
T=280.41 °C
So the final temperature is 280.41 °C.
Answer:
Unmeltedd ice = 308.109 g
Explanation:
Gibbs Free energy:
A systems Gibbs Free Energy is defined as the free energy of the product of the absolute temperature and the entropy change less than the enthalpy change.
Therefore, G = ΔH-TΔS
where G is Gibbs Free Energy
ΔH is enthalpy change
T is absolute temperature
ΔS is entropy change
Here since there is a phase change, therefore G will be 0.
∴ΔH = TΔS
Given: Temperature, T = 0°C = 273 K
Entropy change,ΔS = 600 J/K
Latent heat of fusion of water = 333 J/g
∴ΔH = TΔS
∴ΔH = 273 x 600
= 163800 J
So this is the amount of enthalpy that will be used into melting of ice.
∴ΔH = mass of ice melted x latent heat of fusion of water
Mass of ice melted = ΔH / latent heat of fusion of water
= 163800 / 333
= 491.891 g
This is the mass of ice melted.
And initial amount of ice is 800 g
Amount of ice left after melting = Initial amount of ice - amount of ice melted
= 800-491.891
= 308.109 g
Amount of ice remained after melting = 308.109 g
Seven
The magnitude is pointing towards the origin and is at - 20 degrees. The combination makes 160 with the x axis: C answer
Eight
They keep doing this. They use distance where they should use displacement but they use distance to try and fool you. It's a mighty poor practice.
The distance between the start and end points is the displacement. That "distance" is 180*sqrt(25) = 900 . The actual distance should be 180*4 + 180*3 = 720 + 540 = 1260. That's what a car's odometer or a bicycle odometer would read. the difference is 360.
I really do object to the wording, but what can I do?
Nine
Nine is the same thing as 8.
Displacement = sqrt(400^2 + 80^2)= sqrt(166400) = 408
The actual distance is 400 + 80 = 480
The difference is the answer = 480 - 408 = 72 <<<< Answer
Ten
This is just the displacement magnitude.
dis = sqrt(30^2 + 80^2)
dis = sqrt(900 + 6400)
dis = sqrt(7300)
dis = 85.44 <<<< Answer D
Twelve
Vi = 2.15*Sin(30) = 1.075 m/s
vf = 0
a = - 9.81
t = ?
<u>Formula</u>
a = (vf - vi)/t
<u>Solve</u>
-9.81 = (0 - 1.075)/t
- 9.81 * t = -1.075
t = 0.11 seconds
Thirteen
I'm leaving this last one to you. You need the initial height xo to answer it properly. Judging by the other questions, this one is right.
Edit
That is a surprise! Really quickly
d = 3.2 m
a = - 9.82
vf = 0
vi = ?
vf^2 = vi^2 - 2*a*d
0 = vi^2 - 2*9.81*3.2
vi = sqrt(19.62*3.2)
vi = 8.0 m/s But that is the vertical component of the speed
v = vi/sin(25)
v = 8.0/sin(25) = 11
Answer:
the propagation velocity of the wave is 274.2 m/s
Explanation:
Given;
length of the string, L = 1.5 m
mass of the string, m = 0.002 kg
Tension of the string, T = 100 N
wavelength, λ = 1.5 m
The propagation velocity of the wave is calculated as;
Therefore, the propagation velocity of the wave is 274.2 m/s
