If gold gets hot enough, it will melt. what type of change is this?
a)physical
b)chemical
c)both

yep c, she is right because its melting and your can see it actually happening, and chemical because it is also happening internally (by that i mean internally in the ice.) :)

5 w for 1hr = 5x60x60 joules=300x60=3000x6=18,000j as total energy conversion. efficiency of bulb needed for radiant to thermal within 18000

small = small current large mag large current