Jean used an electronic scale to measure the mass of a rock: 40g. Then through the displacement method, she measured its volume: 10 mL. What is the density of the rock? Group of answer choices

0.25 g/mL

40 g/mL

400 g/mL

4 g/mL

The diagram shows four locations in the electric field of a positive point charge m. at which location is the electric potential the greatest.

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?

What is the role of lenses in microscopy?