There are various properties which are exhibited by substances like physical properties,chemical properties,magnetic properties,electric properties etc.
By simply observing the substance we can not get any idea about the property of a substance.One has to conduct various tests in order to reach at his or her conclusion. The scientific tests provides a better understanding about the nature of substance and the changes that happen under various conditions and parameter.
Answer:

Explanation:
You can consider that the force that acts over the proton is the same to the force over the electron. This is because the electric force is given by:


where E is the constant electric field between the parallel plates, and is the same for both electron and proton. Also, the charge is the same.
by using the Newton second law for the proton, and by using kinematic equation for the calculation of the acceleration you can obtain:

(it has been used that vp^2 = v_o^2+2ad) where d is the separation of the plates, ap the acceleration of the proton, vp its velocity and mp its mass.
By doing the same for the electron you obtain:

we can equals these expressions for both proton and electron, because the forces qE are the same:

Answer:
2 objects with steel or iron
3 objects with mass
Explanation:
Explanation:
neglecting air resistance both will land at the same moment.
both have therefore the same acceleration.