An experiment is performed on an unknown material and produces the given heat curve. The temperature of the material is shown as a function of heat added. Other experiments determine that the material has a temperature of fusion of fusion=235 °C and a temperature of vaporization of vapor=471 °C. If the sample of material has a mass of =9.80 g, calculate the specific heat when this material is a solid, s, and when it is liquid, l.

Consider a system to be two train cars traveling toward each other. what is the total momentum of the system before the train cars collide?   kg • what must the total momentum of the system be after the train cars collide?   kg •  

Select all the correct answers. which three statements about electromagnetic radiation are true?

Acentrifuge in a medical laboratory rotates at an angular speed of 3,700 rev/min. when switched off, it rotates through 54.0 revolutions before coming to rest. find the constant angular acceleration (in rad/s2) of the centrifuge. your response is within 10% of the correct value. this may be due to roundoff error, or you could have a mistake in your calculation. carry out all intermediate results to at least four-digit accuracy to minimize roundoff error. rad/s2