Answer:
In Btu:
Q=0.001390 Btu.
In Joule:
Q=1.467 J
Part B:
Temperature at midpoint=274.866 C
Explanation:
Thermal Conductivity=k=30 (Btu/hr)/(ft ⋅ °F)= 
Thermal Conductivity is SI units:
Length=20 cm=0.2 m= (20*0.0328) ft=0.656 ft
Radius=4/2=2 mm =0.002 m=(0.002*3.28)ft=0.00656 ft
T_1=500 C=932 F
T_2=50 C= 122 F
Part A:
In Joules (J)
Heat Q is:
In Btu:
Heat Q is:
PArt B:
At midpoint Length=L/2=0.1 m
On rearranging:
Answer:
The rate of entropy change of the air is -0.10067kW/K
Explanation:
We'll assume the following
1. It is a steady-flow process;
2. The changes in the kinetic energy and the potential energy are negligible;
3. Lastly, the air is an ideal gas
Energy balance will be required to calculate heat loss;
mh1 + W = mh2 + Q where W = Q.
Also note that the rate of entropy change of the air is calculated by calculating the rate of heat transfer and temperature of the air, as follows;
Rate of Entropy Change = -Q/T
Where Q = 30Kw
T = Temperature of air = 25°C = 298K
Rate = -30/298
Rate = -0.100671140939597 KW/K
Rate = -0.10067kW/K
Hence, the rate of entropy change of the air is -0.10067kW/K
I think it would be the resistor?
Answer:
Explanation:
= Energy for defect formation = 1.86 eV
T = Temperature = 
k = Boltzmann constant = 
The fraction of lattice sites that are Schottky defects is given by
The required ratio is .
Answer:
This question comprises two independent parts, (a) and (b) (a) In the diagram below, the cable connecting the winch A with point B on the railway carriage is being wound in at a constant rate of 2 m/s. Determine, for the instant in time when the angle θ= 60° (i) The velocity vector of the railway carriage (ii) The acceleration vector of the railway carriage The radius of the winch can be considered negligible. (2 marks) (3 marks) (b) The diagram below shows two rotating ‘driving links, OA and BC, connected by a telescoping link AB. Determine the angular velocity vector of the telescoping link AB when it is in the position shown if the driving links have the angular velocities indicated in the diagram. 150 2 rad/s 45 165 Dimensions in millimeters 60 0 2 rad/s
