When you stack three flashlight batteries in the same direction, you get a voltage of 3*1.5 volts = 4.5 volts. what voltage do you get if one of the batteries is turned to face in the opposite direction? a) 0 volts b) 1.5 volts c) 3 volts d) -4.5 volts

Bob camina 200 m sur, luego trota 400 m suroeste, luego camina 200 m en una dirección 30? norte del este. a. dibuje una gráfica de los movimientos de bob. use una regla y transportador. b. use método gráfico y analíitico para hallar el desplazamiento total que bob recorrió. (magnitud y dirección) c. compare los resultados obtenidos por el método gráfico y analítico. (por ciento de diferencia).

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 710 n/m. it is initially at rest on an inclined plane that is at an angle of θ = 23° with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is μk = 0.19. in the initial position, where the spring is compressed by a distance of d = 0.16 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. a) what is the block's initial mechanical energy? b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

Select all the correct answers. which changes will increase the rate of reaction during combustion? decreasing the area of contact between the reactants adding more oxygen to the reaction removing heat from the reaction changing the reactants from solid form to powdered form lowering the exposure of the reactants to air