Why does the horse rider falls forward when a horse at full gallop stops suddenly?

Why does the horse rider falls falls forward when a horse at full gallop stops suddenly ?

Why does a passenger fall forward when he alights from the moving bus ?

Why does a person in a bus tends to fall forward when it stops suddenly?

A rider on horse back falls when horse starts running all of a sudden because

The rider tends to fall backward when a horse start suddenly. This is due to ___________ of ______________.

Why does an opaque body form shadow when light falls on it ?

A person in a bus tends to fall backward, when it starts suddenly?