Un albañil en un andamio deja caer una caja de 2.50 kg desde una altura de 6 m. A) ¿Qué energía cinética tiene la lata cuando está a una altura de 4 m? B) ¿Con qué rapidez llegará la lata al suelo?

Why do different substances have diffrent properties

The base of a 50-meter tower is at the origin; the base of a 50-meter tree is at (0, 50, 0). the ground is flat and the z-axis points upward. the following parametric equations describe the motion of six projectiles each launched at time t = 0 in seconds. (i) r (t) = (50 + t2)k (ii) r (t) = 2t2 j + 2t2k (iii) r (t) = 50 i + 50 j + (50 − t2)k (iv) r (t) = 2t j + (50 − t2)k (v) r (t) = (50 − 2t) i + 2t j + (50 − t)k (vi) r (t) = t i + t j + tk (a) which projectile is launched from the top of the tower and goes downward? at time t = , the projectile hits the ground at point (x, y, z) = . (b) which projectile hits the top of the tree?

Which statements best describe energy? check all that apply. the total amount of energy in the universe remains constant. the total amount of energy in the universe changes constantly. energy cannot be converted from one form to another. energy can be converted from one form to another. energy cannot be created or destroyed. energy can be created or destroyed.