Given:
Temperature of water,
=
=273 +(-6) =267 K
Temperature surrounding refrigerator,
=
=273 + 21 =294 K
Specific heat given for water,
= 4.19 KJ/kg/K
Specific heat given for ice,
= 2.1 KJ/kg/K
Latent heat of fusion,
= 335KJ/kg
Solution:
Coefficient of Performance (COP) for refrigerator is given by:
Max
= 
=
= 9.89
Coefficient of Performance (COP) for heat pump is given by:
Max
= 
= 10.89
Answer:
a) 22.5number
b) 22.22 m length
Explanation:
Given data:
Bridge length = 500 m
width of bridge = 12 m
Maximum temperature = 40 degree C
minimum temperature = - 35 degree C
Maximum expansion can be determined as

where , \alpha is expansion coefficient
degree C
SO, 

number of minimum expansion joints is calculated as

b) length of each bridge

Answer:

Explanation:
Using the expression shown below as:

Where,
is the number of vacancies
N is the number of defective sites
k is Boltzmann's constant = 
is the activation energy
T is the temperature
Given that:

N = 10 moles
1 mole = 
So,
N = 
Temperature = 425°C
The conversion of T( °C) to T(K) is shown below:
T(K) = T( °C) + 273.15
So,
T = (425 + 273.15) K = 698.15 K
T = 698.15 K
Applying the values as:

![ln[\frac {2.3}{6.023}\times 10^{-11}]=-\frac {Q_v}{1.38\times 10^{-23}\times 698.15}](https://tex.z-dn.net/?f=ln%5B%5Cfrac%20%7B2.3%7D%7B6.023%7D%5Ctimes%2010%5E%7B-11%7D%5D%3D-%5Cfrac%20%7BQ_v%7D%7B1.38%5Ctimes%2010%5E%7B-23%7D%5Ctimes%20698.15%7D)

Answer:
$7,778.35
Explanation:
At year 3, the final payment of the remaining balance is equal to the present worth P of the last three payments.
First, calculate the uniform payments A:
A = 12000(A/P, 4%, 5)
= 12000(0.2246) = 2695.2 (from the calculator)
Then take the last three payments as its own cash flow.
To calculate the new P:
P = 2695.2 + 2695.2(P/A, 4%, 2) = 2695.2 + 2695.2(1.886) = 7778.35
Therefore, the final payment is $7,778.35
Answer:
Mechanical average of a wheel = 3
Explanation:
Given:
Radius of wheel = 1.5 ft = 1.5 x 12 = 18 inches
Radius of axle = 6 inches
Find:
Mechanical average of a wheel
Computation:
Mechanical average of a wheel = Radius of wheel / Radius of axle
Mechanical average of a wheel = 18 / 6
Mechanical average of a wheel = 3