Sami pops a helium balloon at a birthday party. what will happen to the particles of helium that were in the balloon?

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.

Adielectric-filled parallel-plate capacitor has plate area a = 30.0 cm2 , plate separation d = 9.00 mm and dielectric constant k = 3.00. the capacitor is connected to a battery that creates a constant voltage v = 15.0 v . throughout the problem, use ϵ0 = 8.85x10-12 c2/n.m2 . find the energy u1 of the dielectric-filled capacitor.

How can you improve the percent yield of copper in this lab? check all possible strategies that will you do so. measure reactants precisely. stir to the reaction take place. chill the reactants before combining them. wait patiently until the reaction completes. make sure to recover as much copper as possible.