In both cases less energy is required
But comparetively Mg require more energy than K
Let's see the electron configuration of Both
- [Mg]=1s²2s²2p⁶3s²=[Ne]3s²
- [K]=1s²2s²2p⁶3s²3p⁶4s¹=[Ar]4s¹
K has only one valence electron so very less ionization enthalpy so less energy required
Mg has 2 so more IE hence more energy required
Answer:
7,79 seconds
Explanation:

You need to use the acceleration formula. A is acceliration,
is change in velocity and t is time.
You need to multiply the formula with t and divide by a and you get
a*t=
t=
/a
after that you just need to insert the numbers
change in velocity is 76.4 minus 0.
acceliration is gravitational acceleration which is 9.81.
After that you get
t=76.4/9.81
t= 7,787971458 s