How much heat in kcal is required to change 0.5 kg of ice, originally at - 10 0 * c into steam at 110 c? constants needed in the problemlatent heat of fusion=79.7 kcal/kg specific heat of ice=0.5 kcal/kg/k ; latent heat of vaporization ation = 539 kcal/kg ; specific heat of water 1.0 kcal/kg/k specific heat of ieam=0.480 kcal/kg

Engineers find a new metal that is stronger than steel but much lighter. this material is also significantly cheaper than what is currently used for most aircraft, available in large quantities, and easy to manufacture. the engineers are excited because this new material will lower the costs of buying and operating airplanes for companies. what is probably the best step for the engineers to make next?

Two resistors r1 and r2 may be connected either in series or parallel across an ideal battery with emf ε. we desire the rate of energy dissipation of the parallel combination to be 8.75 times that of the series combination. if r1 = 105 ω, what are the (a) smaller and (b) larger of the two values of r2 that result in that dissipation rate?

Cathy is pedaling down a steep hill on her bicycle and wants to be able to coast up the next hill, which is 25 meters high, without pedaling. cathy and her bicycle have a mass of 75 kg. assuming her bicycle is 100% efficient, what would her speed have to be?