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About This QuizSolar lights are a simple solution for night-time outdoor lighting. You simply stick them in the ground and they store up their own power during the day and release it at night. See how much you know about solar yard lights by taking this quiz.
What is the main benefit of solar yard lights?
They are cheap.
They are very bright.
No wires are necessary.
The greatest advantage of using solar yard lights is that no messy wiring is necessary to power them.
When installing solar yard lights, how should they be positioned?
Place many lights close together.
Place the lights under direct sunlight.
Solar yard lights depend on sunlight exposure to run. When placing them in your yard, ensure they are positioned where they will receive direct sunlight.
Place the lights in a sheltered area.
Which of the following functions in a similar way to solar yard lights?
Solar yard lights function in a similar manner to satellites. They both store power during the day and release it at night. A satellite stores solar energy while on the sunny side of the Earth and then uses it while on the dark side.
What type of battery do solar yard lights use?
Solar lights usually use AA NiCad batteries.
What sort of light source does a solar yard light use?
LED lights are the light source for solar yard lights.
How does a solar yard light know when it gets dark?
It is set on a timer.
It has a light sensor.
Solar yard lights contain a photo resistor, which is a type of light sensor.
It measures the drop in temperature when the sun sets.
Up to how many volts can a single solar cell produce?
A single solar cell can produce a maximum of 0.45 volts. The amount of current a solar cell can produce will depend on the size of the cell and how much light strikes its surface.
How many solar cells would you find in a typical solar yard light?
You would usually find four solar cells wired in series.
What is the function of a diode in a solar cell?
It allows for slow release of stored energy.
It prevents backflow of current.
A diode is wired directly to the battery in order to prevent the current from the battery flowing back through the solar cell at night.
It increases the amount of current.
What factors affect the amount of charge the NiCad battery will reach?
the length of the day
both of the above
An AA NiCad battery can store a maximum of about 700 milliamp-hours. The battery charges during the day and will reach its maximum charge, unless it is winter and the day is very short or the weather is very overcast.
How long can the NiCad battery operate the LED for?
When fully charged, the NiCad battery can operate the LED for about 15 hours.
How much light will an LED emit compared to a candle?
half the amount of light of a candle
An LED emits about half the amount of light as a candle would. They are mainly used to mark a trail, not to illuminate an area.
the same amount of light as a candle
double the amount of light of a candle
What is a problem with solar cells?
They are very difficult to wire.
They are expensive.
Solar cells are expensive, because they are made from silicon crystals in clean-room conditions.
They need regular replacing.
How are some solar yard lights designed to produce a stronger light?
A halogen bulb is added.
A small halogen flashlight bulb is added to some more expensive solar yard lights to boost their output.
They have a back-up power supply.
They have extra solar cells.
In solar yard lights with a halogen bulb, what causes the halogen light to turn on?
It is on a timer.
It has a light sensor.
It has a motion sensor.
The halogen light is triggered when a motion sensor detects movement. The LED light is on all the time.