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.
It may be time to replace your thermostat is it’s old. They aren’t meant to last forever and an old thermostat may be costing you a lot of money in wasted energy and time spent tinkering with an outdated model. There are great programmable thermostats available now that are easy to use and simple to connect to your existing HVAC system. Click here for more info on programmable thermostats.
Answer:
Explanation:
The self-inductance of a solenoid is defined as:
Here 
is the the permeability of free space, N is the number of turns in the solenoid, A is the cross-sectional area os the solenoid and l its length. We replace the given values to get the self-inductance:
Concave mirrors can make a real image.when the object is away from the mirror it is called real image and when the object is closer to the mirror it is called virtual mirror.
Q: An appliance with a 20 Ω resistor has a power rating of 15.0 W. Find the maximum current which can flow safely through the appliance g
Answer:
0.866 A
Explanation:
From the question,
P = I²R............................. Equation 1
Where P = power, I = maximum current, R = Resistance.
Make I the subject of the equation
I = √(P/R).................... Equation 2
Given: P = 15 W, R = 20 Ω
Substitute these values into equation 2
I = √(15/20)
I = √(0.75)
I = 0.866 A
Hence the maximum current that can flow safely through the appliance = 0.866 A
