Engineering Answers

The inductance of moving iron ammeter in micro henry is given by expression: L=20+5θ-2θ² Where θ is deflection in radians from the zero position. Determine the angular in radians for a current of 10A if the for a current of 5A is 30⁰.Also determine the spring constant

a roller mill or ball mill with a diameter of 3.98 m operating at a net energy loss of 19.5% to reduce a particle with sphericity of 1 from size of 3.98 X10^-3 m to 199.9 X10^-6 m. Calculate the percentage load volume to operate at 70% of critical speed. The mill cannot be operating at more than 1.31m^3 load volume at any given time

A collections of human skulls is divided into three classes A, B and C according to the value of a length-breadth index X. Skulls with X<65 are classified as A (long headed), those with 6570 as C (short headed). The percentages in the three classes in this collection are 58, 38 and 4. Find approximate the mean and standard deviation of X, on the assumption that X is normally distributed.

Draw the shear, moment and axial load diagrams for each member of the frame. The joints at A, B, and C

are pin connected.

https://holooly.com/wp-content/uploads/2021/01/1-507.png

A thermometer reads 95.xy°C and the static correction given in the correction curve is -0.0y°C. Hence,

x = 7 and y = 2

Determine the true value of the temperature.

A wire of diameter D= 2 mm and uniform temperature T has an electrical

resistance of 0.01Ω /m and a current flow of 20 A.

a) What is the rate at which heat is dissipated per unit length of wire? What is

the heat dissipation per unit volume within the wire?

b) If the wire is not insulated and is in ambient air and large surroundings for

which T∞= Tsur= 20oC, what is the temperature T of the wire? The wire

has an emissivity of 0.3, and the coefficient associated with heat transfer

by natural convection may be approximated by an expression of the form,

h= C[(T- T∞)/D]1/4, where C= 1.25 W/m7/4 K

5/4

.

5. Why should acetylene gas cylinders used for gas welding be erected in upright position?

5. Why should acetylene gas cylinders used for gas welding be erected in upright position?