Question

Why tip of pin is sharp & head is broad

Answer 1

the tip of a pin is sharp because as area of the pin becomes less then more pressure will be exerted and the pin will easily penetrate into the wall or anything else.

Answer 2

     The tip of a pen is made to be very small, sharp, thin and pointing.  This is to make it penetrate some thing like a cloth, paper etc...  When we want to stitch some thing, we need the needle to penetrate in to that material... so it is sharp.

    The head is broad , so that we can hold the needle at the head.  To have a good grip, the needle is broad.. also, the needle used for stitching needs to have a thread passing through  it... there is a hole through it.. so the head is large to allow for the hole..