The amount of heat needed to melt the block of lead is [tex]5.4\cdot 10^4 J[/tex]
Explanation:
The amount of heat needed to melt a solid substance already at its melting point is given by the equation
[tex]Q=m \lambda_f[/tex]
where
m is the mass of the substance
[tex]\lambda_f[/tex] is the specific latent heat of fusion
In this problem, we have a block of lead already at its melting point, [tex]327^{\circ}C[/tex]. Its mass is
m = 200 g = 0.2 kg
and its specific latent heat of fusion is
[tex]\lambda_f = 2.7\cdot 10^5 J/kg[/tex]
Therefore, the amount of heat needed for the block to completely melt is
[tex]Q=(0.2)(2.7\cdot 10^5)=5.4\cdot 10^4 J[/tex]
Learn more about specific heat:
brainly.com/question/3032746
brainly.com/question/4759369
#LearnwithBrainly
