Dois fios longos retilíneos, estendidos no plano do papel, se cruzam perpendicularmente sem que haja contato elétrico entre eles. Esses fios são percorridos por correntes de intensidades i1 e i2. Sendo i1 a corrente que passe pelo fio vertical com sentido norte-sul, e i2 a corrente que passa pela espira horizontal no sentido oeste-leste. Nestas condições, em quais regiões é possível ser nulo o campo magnético resultante dos dois fios?

Acar of mass m goes around a banked curve of radius r with speed v. if the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force on the car from the road is equal in magnitude to 101) a) mv2/r b) mg/2. d) mg e) tan[v2/(eg)]

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.

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 •