Lets se
And


So

If spring constant is doubled mass must be doubled
No. the answer to the question if can an argon atom undergo vibrational motion is no. it can not even spin either. the argon atom, or the argon is a chemical element that is the third most abundant gas in the earth's atmosphere. it is ore than twice as abundance as water vapor. Thank you for this question.
Explanation:
According to formula
g = GM/R^2
when mass is halved the value of g becomes half but when radius is halved the value of g increases 4 times.
As a result of both value of g becomes twice.
Answer:
Part a)

Direction of force is along the motion of charge
Part b)

direction of electric field is along the direction of motion
Explanation:
Part a)
As we know that the change in electric potential energy is equal to the work done by electric field


now from the equation of work done we know that



Direction of force is along the motion of charge
Part b)
As we know the relation between electrostatic force and electric field given as



direction of electric field is along the direction of motion