Part A A U.S. penny has a diameter of 1.9000 cm at 20.0 C . The coin is made of

Question

Part A

A U.S. penny has a diameter of 1.9000 cm at 20.0 C . The coin is made of a metal alloy (mostly zinc) for which the coefficient of linear expansion is 2.6×105K1 .What would its diameter be on a cold night in the mountains of Greenland (-52 C )? (cm)

Part B

A blacksmith cools a 1.20-kg chunk of iron, initially at a temperature of 650.0C , by trickling 15.2 C water over it. All the water boils away, and the iron ends up at a temperature of 120.0C . How much water did the blacksmith trickle over the iron?

Explanation / Answer

(A) D = Do[1 + alpha deltaT ]

D = (1.9000 cm) [ 1 + (2.6 x 10^-5)(-52- 20)]

D = 1.8964 cm

(B) Energy gained by water = m Cwater deltaT + m Lv

= m (4.186) ( 100 - 15.2) + m x 2258

= 2612.97m

energy lost by iron = m Ciron deltaT

=1.20 x 0.385 x (650 - 120 )

= 244.86 kJ

Applying energy conservation, 2612.97m = 244.86

m = 0.0937 kg Or 93.7 grams of water

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.