Given,
mass m = 1.5 kg
initial temp t1 = 30°C
heat supplied Q = 7.5 *104 J
specific heat capacity s = 1000 J/ kg°C since pressure cookers are made of allow and this is the specific heat capacity of an alloy.
final temperature t2 = ??
By using formula,
Q= ms(t2-t1)
\(t2-30=\frac{75}{1.5}\)
t2 = 50+30
t2 = 80°C