An 8.10 kilogram box of mass is kept at a height of 0.99 meters above ground level. what is the potential energy of the box? (given g = 9.8 meters/second2). a. 68 joules. b. 79 joules. c. 81 joules. d. 99 joules. e. 1.0 × 102 joules

Física: un futbolista patea hacia el arco con una velocidad de 15m/ah, calcular: a)el alcance para un ángulo de tiro de 25? , b) el tiempo que el balón permanece en el aire.

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.

When a light bulb shines, it gives off light energy and energy. a. heat b. potential c. chemical d. electrical