The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. if all the energy obtained from burning 1.21 pounds of butane (fuel value is 10.85 kcal/g) is used to heat 123.0 kg of water at an initial temperature of 18.0 °c, what is the final temperature?

66°C

Explanation:

Energy obtained from burning 1.21 pounds of butane gives a fuel value of 10.85 kcal/g

mass of water = 123.0kg

Initial temperature = 18.0°C

Final temperature = α

Energy released from burning butane is used to heat water to the final temperature

Energy released = Q released

Q released = 1.21 * 453.59 * 10.85

= 5954.96J

Energy needed = Q needed

Q needed = 123 * 1 * (α - 18)

= 123(α - 18)

Q needed = Q released

123(α - 18) = 5954.96

α - 18 = 5954.89/123

α - 18 = 48.41

α = 48.41 + 18

α = 66.41

α = 66° C (approximately)

a person with a mass of 106kg has a weight of 1060n

energy stored in the capacitor= 9.72 x 10⁻⁴ j

explanation:

the energy stored in the capacitor is given by

e= 1/2 c v²

e= energy stored

c= capacitance= 1.5 µc= 1.5 x 10⁻⁶f

v= potential difference=36 v

so energy stored= e= 1/2 (1.5 x 10⁻⁶) (36)²

energy stored= 9.72 x 10⁻⁴j