Resolución del siguiente ejercicio por favor: Una partícula alfa, el núcleo de un átomo de helio, tiene una masa de 6.64 X 10~-27 kg y una carga de +2e , ¿Qué magnitud y dirección del campo eléctrico balancearán su peso?

Astudent wears sunglasses to her read a book more easily which wave interaction occurs as light passes from the air into the plastic lenses? a polarization b.refraction c.diffraction d. interference

It is really hard for me right know

Consider a 1000 w iron whose base plate is made of 0.5 cm thick aluminum alloy 2024-t6 (ρ = 2770 kg/m3 and cp = 875 j/kg°c). the base plate has a surface area of 0.03 m2. initially, the iron is in thermal equilibrium with the ambient air at 22°c. assuming 90% of the heat generated in the resistance wires is transferred to the plate, determine the minimum time needed for the plate temperature to reach 200°c.