Astudent stands on a motionless box. when drawing the free body diagram for the box, should the normal force arrow be drawn the same as the gravity vector arrow?

The normal force arrow should have same length of the gravity arrow, but opposite direction (so, upward)

Explanation:

The box is motionless: this means that its velocity is zero, and also that its acceleration is zero.

Zero acceleration means that the net force on the box is also zero, according to Newton's second law:

This means that the two forces acting on the box (gravity and normal force) must balance each other to produce a zero net force: therefore, the two forces must have same magnitude (so, the two arrows must have same length), but opposite direction (and since gravity acts downward, the normal force must be upward).

what type of charge does it have? negative

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.