Later in the movie Hancock tries to help Walter the beached

Later in the movie, Hancock tries to help Walter, the beached Grey Whale, by grabbing his tail and throwing him back into the ocean. At his highest point, Walter - all 30 tons of him -made it up to 120 feet in the air (before his untimely demise due to a high-speed impact upon a boat mast and over-fishing of krill by humans, but mostly due to the high-speed impact upon a boat mast). At the apex of his trajectory, calculate Walter\'s gravitational potential in units of kW-hr kJ Btu Nutritional calories, kcal Slices of Costco pizza

Solution

Weight (mg) of the whale is 30 tons = 30000 kg-f or 30000 N

1 ft = 0.3048 m

120 ft = 120*0.3048 = 36.576 m

Potential energy of the whale at this point is weight*height

Potential Energy = 30000*36.576

Energy = 1097280 Joules

a) 1 J/s = 1 W

3600 J = 1 W-hr

3600*1000 = 1 kW-hr

1097280 Joules = 1097280 / (3600000)

Energy= 0.3048 kW-hr

b) 1000 J = 1 kJ

1097280 Joules = 1097.280 kJ

c) 1 kJ = 0.9478 Btu

1097.280 kJ = 1040.02 Btu

d) 1 kJ = 0.239 kcal

1097.280 kJ = 262.256 kcal

e) 1 slice of costco pizza contains 700-800 cal

Taking average = 750 cal = 0.750 kcal

no. of slices = 262.256 kcal / 0.750 kcal

No. of slices = 349.67 slices