I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

Once upon a time, there was a castle on a square island. The entire island was surrounded by a 14m wide trench. The Romans had wanted to invade the castle and had brought a few wooden planks along with them to facilitate themselves in crossing the moat. The planks were however found to be only 13m long.

The Romans still managed to cross the trench. How did they do it?

A Car is crossing a bridge 2 miles long. The bridge can only hold 10000 lbs, which is the exact weight of the car. The Car makes it half way across the bridge and stops. A bird lands on the car. Does the bridge collapse? Explain.

I start and end with 500 and carry a 5 in my heart. But I require the first letter and the first number to be complete. I am the name of a King.

Who am I ?

Can you move 2 matchsticks to form four equal sized squares.

Why is the Hole below a Lock?

What time is it when an elephant sits on a fence?

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

In the figure, you can see nine stars. What you have to do is connect all of them by using just four line and without lifting your hand i.e. in a continuous flow.

10+10 and 11+11 can give you the same answer.

Explain how?