Usha stopped her car suddenly when 'X' light signal poped up on the road. After a few seconds, she moved her car due to the 'Y' light signal. What are these 'X' and 'Y' light signals?

Q. Aman was driving in his car, he suddenly stopped looking at light ‘A’ on the traffic signal. And he left when he saw light ‘B’ on the traffic signal. What colours are shown by lights ‘A’ and ‘B’?

Q. Meeta's father was driving her to the school. At the traffic signal she noticed that each traffic light was made of many tiny lights instead of a single bulb. When meeta asked this question to her father. he explained the reason for this.
Answer the following based on above information:
(i) What were the values displayed by meeta and her father?
(ii) What answer did meeta's father give?
(iii) What are the tiny lights in traffic signals called and how do these operate?

Q. Why are red coloured lights are used in traffic signals to stop the vehicles?

Q. A motor car travels 175 distance from a place A to place B, at a uniform speed 70km/hr passes though all ten green traffic signals. Due to heavy traffic it stops for one minute at first signal, 3 minutes at second signal, 5 minutes at third signal and so on stops for 19 minutes at tenth signal. How much total time it takes to reach at the place B. Solve by suitable mathematical method.

Q. Light sensitive cells on gets activated whenever light falls on it and generate signals.