The position of the first ball is

while the position of the second ball, thrown with initial velocity
, is

The time it takes for the first ball to reach the halfway point satisfies



We want the second ball to reach the same height at the same time, so that




Answer:
T_finalmix = 59.5 [°C].
Explanation:
In order to solve this problem, a thermal balance must be performed, where the heat is transferred from water to methanol, at the end the temperature of the water and methanol must be equal once the thermal balance is achieved.

where:

mwater = mass of the water = 0.4 [kg]
Cp_water = specific heat of the water = 4180 [J/kg*°C]
T_waterinitial = initial temperature of the water = 85 [°C]
T_finalmix = final temperature of the mix [°C]

Now replacing:
![0.4*4180*(85-T_{final})=0.4*2450*(T_{final}-16)\\142120-1672*T_{final}=980*T_{final}-15680\\157800=2652*T_{final}\\T_{final}=59.5[C]](https://tex.z-dn.net/?f=0.4%2A4180%2A%2885-T_%7Bfinal%7D%29%3D0.4%2A2450%2A%28T_%7Bfinal%7D-16%29%5C%5C142120-1672%2AT_%7Bfinal%7D%3D980%2AT_%7Bfinal%7D-15680%5C%5C157800%3D2652%2AT_%7Bfinal%7D%5C%5CT_%7Bfinal%7D%3D59.5%5BC%5D)
Voltage = Current (I) × Resistance (R)
V = 10 × 28.5 = 285v