An ‘anti-drowning’ bracelet is a water safety device. It contains a CO2 cartridge that can quickly inflate an airbag to help a diver rise to the surface in an emergency situation. Robert Irwin (son of "The Crocodile Hunter" Steve Irwin) is snorkeling at the Great Barrier Reef (rhoseawater = 1029 kg/m3). He swims 5.0 m below the surface of the water when there is an emergency and he activates the bracelet. The mass of Robert and his gear is 69.2 kg and the volume of salt water he displaces is 0.07 m3 before the safety device is activated. Once he activates the device, it inflates to a volume of 0.01 m3.

How long would it take him to get to the surface assuming he starts from rest (ignore any drag forces from the water)?

What is hidden during a lunar eclipse? isn't the moon hidden?

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.

Ineed asap! list 3 examples in which friction us or makes things easier in our daily life. explain the effect of friction for each. *make sure you explain the effect of friction for each example! *