A 0.4kg ball is thrown straight up into the air and reaches a maximum altitude of 20m. Taking its initia position as the point of zero potentia energy and using energy methods, find (a) its initia] speed, (b) its total mechanical energy, and (c) the ratio of its kinetic energy to the potential energy when the ball is at an altitude of 10m.​

answer: a) y=-8x+5

a) m= -8

b) m= -2

c) m= 7

d) m= 6

laticia draws the diagram below to show earth’s magnetic field.

answer

the arrows to the right of earth should point up.

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.