Problem 4: a 1 , 5kva, 240/120 v, 60 hz transformer has a core loss of 100 w at rated voltage and copper loss of 120 w at rated current. calculated the efficiency for the following load condition: (a) it is delivering 5 kva at rated voltage and a power factor of 0.8. (b) it is delivering 2 kva at rated voltage and a power factor of 0.8.

Explain the difference laminar and turbulent flow. explain it with the shear stress and the velocity profiles.

When at a point two solid phase changes to one solid phase on cooling then it is known as a) eutectoid point b) eutectic point c) peritectic point d) peritectoid point

Asingle-geared blanking press has a stroke of 200 mm and a rated capacity of 320 kn. a cam driven ram is assumed to be capable of delivering the full press load at constant force during the last 15 percent of a constant-velocity stroke. the camshaft has an average speed of 90 rev/min and is geared to the flywheel shaft at a 6: 1 ratio. the total work done is to include an allowance of 16 percent for friction a) estimate the maximum energy fluctuation b) find the rim weight for an effective diameter of 1.2 m and a coefficient of speed fluctuation of 0.10