A yellow arrow traffic light means that you should yield in the direction you are going. These are often in place when you are turning left.
A yellow traffic light means to slow down or stop completely. When the light is yellow it is about to change to red in a few seconds. Contrary to popular belief by many drivers yellow does not mean speed up.
owdown
On traffic lights it means slow down.
The yellow *traffic* light means to slow down and get ready to stop because it is about to turn to the red light.
A yellow arrow traffic light means that you should yield in the direction you are going. These are often in place when you are turning left.
A steady yellow light typically indicates that the traffic signal is about to turn red. It serves as a warning for drivers to prepare to stop before the light changes.
Yellow light
By "amber" I assume you mean yellow. A yellow traffic light indicates that your "right of way" is ending within the next couple seconds. When the light turns yellow you shouldn't enter the intersection if you haven't already, unless you've reached "The point of no return". It's not illegal to go through the intersection while the traffic light is yellow, but if you can stop you should, if you can't stop then go through the intersection (determined by your own judgement). A yellow light is basically a warning of a red light coming, where it is illegal to proceed through the intersection. The duration of a yellow light depends on the road the traffic light is governing. For a side road the traffic light may only show a yellow for around 3 seconds, for a major road such as a state road or US Highway, the traffic light may show a yellow for 4-6 seconds. These timings all depend on the road that the traffic light is governing and what the speed limit is for that road.
Yes, light will scatter after striking a yellow traffic light. The yellow color of the light is due to selective absorption and scattering of certain wavelengths, causing only yellow light to be reflected or transmitted while the rest is absorbed.
In the U.S.A it means you have the right of way but proceed with caution.
Yellow, then red is the patterns of the traffic lights.