Objects A and B have the same mass of 3.4 kg and are at their melting points. They melt when 4.9 × 104 J of heat is added to A and when 11 × 104 J is added to B. (a), (b) Determine the latent heat of fusion for the substance from which each object is made. (c) Find the heat required to melt object A when its mass is 6.8 kg.

LfA= 14411.7J/kg,

LfB= 32352.9J/kg,
QA= 98„e103J

To determine the latent heat of fusion for the substance from which objects A and B are made, we can use the equation:

Q = mL

where Q is the heat added, m is the mass, and L is the latent heat of fusion.

For object A, we know that when 4.9 × 10^4 J of heat is added, it melts. So we can set up the equation:

4.9 × 10^4 J = 3.4 kg * L

Solving for L, we get:

L = (4.9 × 10^4 J) / (3.4 kg)
L ≈ 14411.76 J/kg

Therefore, the latent heat of fusion for the substance from which object A is made is approximately 14411.76 J/kg.

For object B, we know that when 11 × 10^4 J of heat is added, it melts. So we can set up the equation:

11 × 10^4 J = 3.4 kg * L

Solving for L, we get:

L = (11 × 10^4 J) / (3.4 kg)
L ≈ 32352.94 J/kg

Therefore, the latent heat of fusion for the substance from which object B is made is approximately 32352.94 J/kg.

To find the heat required to melt object A when its mass is 6.8 kg, we can use the same equation:

Q = mL

However, since the mass of object A is now 6.8 kg, we substitute this value into the equation:

Q = 6.8 kg * L

Substituting the previously calculated value of L for object A (approximately 14411.76 J/kg):

Q = 6.8 kg * 14411.76 J/kg
Q ≈ 97958.08 J

Therefore, the heat required to melt object A when its mass is 6.8 kg is approximately 97958.08 J.