A45-n brick is suspended by a light string from a 2.0-kg pulley. the brick is released from rest and falls to the floor below as the pulley rotates through 5.0 rad. the pulley may be considered a solid disk of radius 1.5 m. what is the angular speed of the pulley?

Aspring with an unstrained length of 0.071 m and a spring constant of 2.6 n/m hangs vertically downward from the ceiling. a uniform electric field directed vertically upward fills the region containing the spring. a sphere with a mass of 5.29 10-3 kg and a net charge of +7.2 µc is attached to the lower end of the spring. the spring is released slowly, until it reaches equilibrium. the equilibrium length of the spring is 0.058 m. what is the magnitude of the external electric field?