In a closed system that has 85 J of mechanical energy, the gravitational potential energy of a weight being lowered by a pulley decreases from 12 J to
9 J. How does the system's kinetic energy change if there is no friction?
O A. It decreases from 76 J to 73 J.
O B. It increases from 85 J to 94 J.
O c. It decreases from 85 J to 76 J.
O D. It increases from 73 J to 76 J.

Aseries circuit consists of a resistor with r = 20 ? , a capacitor with c = 0.01 f, and a decaying battery with e = 300e? 5t. if the initial charge is 0, find the charge as a function of time t

What happens when chlorine reacts with bromine? a. electrons move from the chlorine atoms to the bromine atoms. b. electrons move from the bromine atoms to the chlorine atoms. c. electrons are shared between the chlorine atoms and the bromine atoms. d. electrons become delocalized among the atoms.

Will give brainliest! jay rides his 2.0-kg skateboard. he is moving at speed 5.8 m/s when he pushes off the board and continues to move forward in the air at 5.4 m/s. the board now goes forward at 13 m/s.a. determine jay’s mass.b. determine the change in the internal energy of the system during this process.(express your answer to two significant figures and include the appropriate units.)