Answer: when a circuit is completed (it allows the flow of electrons which causes the light bulb to produce light).
Explanation:
A circuit is described as an electrical setup that is consists of a light bulb, a switch, a wire, a battery which is arranged to allow the flow of electric current. The major components of the electrical circuit includes:
--> The BATTERY which is the source of voltage to the circuit,
--> the WIRE which is the conductive path,
--> the LIGHT BULB which is the load that needs electrical power to operate and
--> the SWITCH which is the controller.
When a circuit is COMPLETED when electrons can flow from one end of a battery all the way around, through the wires, to the other end of the battery. Along its way, it will carry electrons to electrical objects that are connected to it like the light bulb and make it to produce light.
There are different types of electric circuit which are designed to create a conductive path of current or electricity. They include:
--> closed circuit
--> open circuit
--> short circuit
--> parallel circuit
--> series circuit.
Fossil fuels . . . coal, oil, natural gas
Among primitive cultures, wood is an important source.
Answer:
Explanation:
information we know:
Total force: 
Weight: 
distance: 
vertical component of the force: 
-------------
In this case we need the formulas to calculate the components of the force (because to calculate the work we need the horizontal component of the force).
horizontal component: 
vertical component: 
but from the given information we know that
so, equation these two and
and we know the force , thus:
now we clear for 
the angle to the horizontal is 15.466°, with this information we can calculate the horizontal component of the force:
whith this horizontal component we calculate the work to move the crate a distance of 4 m:
the work done is W=173.48J
Check the power source. Your thermostat may just not be connected right or at all. A blown fuse, tripped circuit breaker or dead batteries will prevent the thermostat from turning on your furnace.
Dirty thermostat? That’ll cause issues. Clean up any dust, dirt, spider webs and other debris. Any of these things can coat the inside of the thermostat and interfere with both electrical and mechanical functions of the thermostat. Put this on your get-ready-for-winter cleaning list. Just use a soft, clean brush to clean the inside components gently. Don’t get anything wet. Also you can use a can of compressed air, such as is used for electronics, to clear debris.
Check for any loose wires or terminal screws inside the thermostat. Make sure wires aren’t corroded or detached. Never remove the thermostat cover without removing the batteries or turning off the power at the fuse or breaker box. Tighten screws and secure loose wires if needed.
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Answer: C. 12.6
Explanation: 2*pi*1.8= 11.304
11.304/0.9= 12.56
