do batteries produce or make energy

Why should seat belts not be mandatory quick plz

Will mark as brainliest how does a catapult increase the trajectory of an object? ps. answer as if u were a 5th grader

Aspring is used to stop a 50-kg package which is moving down a 20º incline. the spring has a constant k = 30 kn/m and is held by cables so that it is initially compressed 50 mm. knowing that the velocity of the package is 2 m/s when it is 8 m from the spring and neglecting friction, determine the maximum additional deformation of the spring in bringing the package to rest.