The torque-speed curve of a 3-phase ac motor nema design type d can be approximated with the parabola: t=-410-5n2+0.0059n +100 where t is in nm and n is in rpm. the motor drives the drum of a hoist (see fig. 5-36), via a gear reducer with the reduction ratio i=60: 1. find the steady state ascending speed in m/s of a crate with mass m=1500 kg, knowing that the drum has a radius of 180 mm. consider that:

The momentum of an isolated system is conserved a) only in inelastic collisions. b) only in elastic collisions. c) in both elastic and inelastic collisions

For problems 1-3, consider a simple dc brush motor with a permanent magnet stator. with an an consider a simple dc brush motor with a permanent magnet ae supply voltage of 100 v, the no-load speed of the motor is 1000 rpm. this motor can provide a torque of 1.9 n-m at 800 rpm drawing a current of 2 a current are both zero at no load.) 1. with an armature supply voltage of 100 v, the motor is operated at 900 rpm. what is the motor torque? what is the mechanical power delivered by the motor? what is the current draw? what is the electrical power input? what is the energy efficiency of the motor? with an armature supply voltage of 100 v, the motor is operated at 1100 rpm (where it acts as a generator). what torque input is required? what mechanical power is required what current is generated? what is the electrical power generated? what is the energy efficiency of the motor acting as a generator? 2. with an armature supply voltage raised to 120 v, the motor is operated at 1000 rpm. what is the no-load speed? what is the motor torque? what is the mechanical power delivered by the motor? what is the current draw? what is the electrical power input what is the energy efficiency of the motor? 3.

Aweight lifter raises a 1600 n barbell to a height of 2.0 meters. how much work was done? w = fd question 6 options: 3000 joules 30 joules 320 joules 3200 joules