Answer / www.isamqa.com

D - room heater

Answer / rafaqat

Well!!!! close loop system is kind of atumatic system that
have a feed back device which measure the actual value and
then feed this value back to controller then controller
compare the setpoint & the actual value (get from feed back
device)after this control generate + or - signals/
correction to final control element ( that is responsible
for controling the variable quantities).

so if your system have a controller with feedback device,
final control element then it will be a close loop system

Answer / carl_ellis

A room heater has a thermostat which senses room
temperature and turns the heater elements on or off, as
needed. It is close loop control.

A washing machine can have a closed loop feedback loop, for
example, water level, where a knob sets water level desired
[setpoint], a sensor detects level and turns off water
valve when satisfied. But the overall wash, soak, rinse,
empty, fill, spin functions are sequenced on a timed basis,
which is classic, open loop, non-feedback control.

Likewise a traffic light system can sense the presence of a
vehicle at an intersection, which enables an upcoming light
change, but the sequences of light changes are timer based,
open loop, non-feedback control.

Carl Ellis
Measure First

Answer / uday

A) respiratory System is a close loop system.

Vertebrates have closed circulatory systems. Their blood flows through blood vessels (arteries, veins and capillaries) and they have a heart to push the blood around their body. The human circulatory system is a closed system.

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