Answer: 35
Explanation:
Given the following :
M = 0.5 kg
Power of heater = 100W
From the graph ;
Time (t) = 7seconds
Change in temperature(Dt) = t2 - t1
Where t2 = 70°C, t1 = 30°C
Dt = (70 - 30)°C = 40°C
Recall Q = iVt
IV = power
Q = mcDt
c = specific heat capacity of liquid
mcDt = ivt
mcDt = power × t
0.5 × c × 40°C = 100 × 7
20°C × c = 700 J
c = 700 J/ 20°C
c = 35 J / kg°C
