During which age was fire first used for heating, cooking, and protection? -Information/Digital age
- Middle ages
- Bronze age
- Stone age

Derive the correction factor formula for conical nozzle i=-(1+ cosa) and calculate the nozzle angle correction factor for a nozzle whose divergence hal-fangle is 13 (hint: assume that all the mass flow originates at the apex of the cone.

An electric motor is used to drive a power press which makes steel turning moment diagrams 323 pressings from a metal sheet. the motor runs at a mean speed of 50 rev/s. the torque required is 10.0nm for 0.2s, followed by 1.0nm for0.3 s with this sequence then being repeated. what is the minimum power required of the motor and the moment of incrtia required for the t1ywhcel if the speed fluctuations are to be restricted to 1.5%?

Explain the strain-hardening phenomenon on the basis of dislocation - dislocation strain field interactions. also, briefly describe what generally happens to the ductility of a metal that has been strain hardened (i. e. does strain hardening make a metal more ductile or