4 A metal wire of length 1cm and of uniform diameter has a
resistance 0.8ohms. What is
the resistance of a 50 cm.
wire coil made of the
same material but having twice it's diameter.

Lexy is correct because angle r is between the incident wave,  n  = 0, and a diffracted wave.

I'm having some difficulty seeing the diagram clearly.but the question says there's a net inward force on the object.so we know right away,  from newton's 2nd law of motion, thatthat baby is accelerating.  it doesn't even matter which way thenet force is pointing.  if there's any net force, then either theobject's speed or else its direction must be changing.