If you drop a 15 kg iron bar and a 5 kg bag of cotton from a height of 50 meters which will reach the ground first?

When I asked a girl's name she told me her name is the date '07/09/2001'.

I thought for a few seconds and then I got her name. Do you?

I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Do you know who was buried in John's tomb?

One night, a man runs away from home. He turns left and keeps running. After some time he turns left again and keeps running. Later, he turns left one more time and runs back home—but when he gets home, he finds a man in a mask. Who was the man in the mask?

Below, you can see some coding:
January = 1017
February = 628
March = 1335
April = 145
May = 1353
June = 1064
July = 1074
August = 186

Now deciphering the way it has been coded, can you find out how September will be coded?

A famous swimmer can swim downstream in a lake in exactly 40 minutes with the lake current.
He can swim upstream in that lake in exactly 60 minutes against the lake current.
The length of the lake is 2 km.

How long he can cover the distance of one side at a still lake with no current?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?