A58-kg boy swings a baseball bat, which causes 0 0.140-kg baseball to move toward third base with velocity f 38.0 m/s. calculate the kinetic energy of the baseball(rounding your answer to the integer)

Three point charges, two positive and one negative, each having a magnitude of 20 μc are placed at the vertices of an equilateral triangle (30 cm on a side). what is the magnitude of the electrostatic force on the negative charge

Consider a system with two masses that are moving away from each other. why will the kinetic energy differ if the frame of reference is a stationary observer or one of the masses?

Why does the equilibrium position of the spring change when a mass is added to the spring? will the mass oscillate around the new equilibrium position of the spring or the previous position without a mass attached to the spring? if the equilibrium position of the spring changes by 20 cm (assuming no initial mass) when a mass is added to the spring with constant 4.9 kg/s^2, what is the mass of the object attached to the spring?