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QUIZZES

The Ultimate Dimmer Switch Quiz
by Staff
A dimmer switch allows you to create romantic ambience at the touch of a button. Take this quiz and find out if you know how it performs its mood-setting magic.

• 1955
• 1959
• 1962

### What is the average life expectancy of a dimmer switch unit?

• more than 10 years
• more than 20 years
• more than 30 years

### What is the name of the component that dims the light in older types of dimmer switches?

• variable resistor
• capacitor
• transformer

### What is a conductor choke?

• a small transformer
• a coil of wire around an iron core
• a device that does not conduct energy well

### What is the disadvantage of older resistive-only dimmers?

• The light bulb burns out faster.
• The light tends to flicker.
• There is a lot of heat from the dimmer.

### Is there an energy-use advantage when you compare the older resistive-only dimmers to the newer models?

• Old-style dimmers use more energy.
• Old-style dimmers use less energy.
• Old-style dimmers use the same energy as the new type.

### How do modern dimmers control the brightness of the light?

• by shutting the voltage off and on rapidly
• by changing the voltage using a transformer
• by using two variable resistors instead of one

### In the U.S., how many times a second does alternating current go from positive to negative?

• 50 cycles a second
• 60 cycles a second
• 70 cycles a second

• two times
• three times
• four times

• 60 times
• 120 times
• 180 times

### What does the turn-on value regulate?

• the speed of the electric current coming into the light
• the brightness of the light
• the amount of electricity being used by the light

### What happens to the light bulb when the dimmer is switching the light on at its fastest?

• It is as dim as possible.
• It is as bright as possible.
• It is not on at all.

### What component is present in both modern and older types of dimmers?

• firing capacitor
• choke coil
• variable resistor

### How does the variable resistor work in a modern dimmer?

• It delays the current.
• It speeds up the current.
• It has no effect on the current.

### When a dimmer's variable resistor arm is all the way to the right, how bright should the bulb be?

• the brightest level
• half as bright as it can be
• the dimmest level

### What could be the cause of buzzing from a cheap dimmer switch?

• heat from the variable resistor inside the switch
• the switch cover not being flush against the wall
• sudden voltage jumps from chopping the electric current

### You installed a new dimmer, and now your TV is making funny noises. What went wrong?

• You didn't properly disconnect the electricity to the wiring before installing the dimmer.
• You accidentally wired the dimmer switch to the same electrical line that runs to the TV.
• You purchased a cheap dimmer that is poorly designed.

### Modern dimmers contain a component called a triode alternating current switch (triac) that actually does the work to dim your lights. What does the triac do to the electric current to achieve a dimming effect?

• It reduces radio interference, such as buzz, caused by dimmer components.
• It switches alternating current on and off so fast it makes a light appear dim to the human eye.
• It acts as a firing capacitor to send current to an incandescent bulb.

### How does the dimmer used to control stage lighting differ from cheaper residential dimmer switches?

• The triac in a stage lighting dimmer is much bigger and has a higher tolerance to extreme conditions.
• These dimmers are essentially the same inside except the components are hardier.
• Stage dimmers must be noise free, so they contain a more expensive device called an autotransformer to reduce current to the lamps instead of a triac.

### How do touch-pad dimmers differ from regular modern dimmers?

• They function the same on the inside.
• They employ autotransformers instead of triacs.
• They combine an autotransformer and a triac.
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