The answer is Thermal Energy :)
X is usually representing time so years, days, etc
Lovely song just asking is there a question so I don't get hate for not knowing rather there's a question or not
Answer:
The greatest acceleration when the unbalanced force is applied will be experienced in :
A) The box with a mass of 2 kg
Explanation:
According to second law of motion the external unbalanced force is directly proportional to rate of change of momentum.
F = (Final momentum - initial momentum)/time
or
Force is equal to the product of mass and acceleration
F = m x a
Here a= acceleration
m = mass of the object
If Force is constant then acceleration is inversely proportional to mass

A) The box with a mass of 2kg
F = 8 N

a = 4 m/s2
B) The box with the mass of 4kg

a = 2 m/s2
C) The box with a mass of 6kg

a = 1.33 m/s2
D) The box with a mass of 8kg

a = 1 m/s2
Answer:
THE FINAL TEMPREATURE OF IRON SWORD IS
1331°C