A steel wire with 5 kg masses on each end is draped over a block of ice at -1 C. The wire's contact area with the ice is about 2 x 10^-5 m^2. (a) Estimate the pressure under the wire. (b) By how much does this lower the melting point, and will the wire cut through? Solution: (a) Force = 2 x 5 x 9.8 = 98 N. Pressure = F/A = 98 / (2 x 10^-5) = 4.9 x 10^6 Pa, about 48 atm. (b) Melting-point lowering = 48 x 0.0075 = 0.36 C, so ice melts at about -0.36 C. Since the block is at -1 C, which is colder, the wire will NOT cut through - the classic demo needs ice very close to 0 C.