a compound strip of brass and iron 10cm long at 20c is held horizontally with the iron uppermost. when heated from below with a bunsen burner. the temperature of the brass is 820c and that of the iron is 770c. calculate the difference in length of the iron and the brass( coefficient of linear expansion of brass and iron are 0.000019c and 0.000012c respectively ​

What is special about a dc circuit ?

Electric field of the earth. the earth has a net electric charge that causes a field at points near its surface equal to 150 n> c and directed in toward the center of the earth. (a) what magnitude and sign of charge would a 60-kg human have to acquire to overcome his or her weight by the force exerted by the earth’s electric field? (b) what would be the force of repulsion between two people each with the charge calculated in part (a) and separated by a distance of 100 m? is use of the earth’s electric field a feasible means of flight? why or why not?

Which of the following best describes internal energy? a. the difference between the kinetic and potential energies of the particles in a system b. the sum of the kinetic and potential energies of the particles in a system c. the sum of the kinetic and thermal energies of the particles in a system d. the difference between the kinetic and thermal energies of the particles in a system