The specific weight of the oil is 7.72 N/L, and the specific gravity is approximately 0.79, which is not one of the options provided, suggesting an error in the choices given.
To calculate the specific weight and specific gravity of oil in a barrel, we first need to deduct the weight of the barrel itself from the total weight to find the weight of the oil alone. The weight of the oil is given by the total weight minus the weight of the barrel, which is 1.50 kN - 119 N = 1.381 kN or 1381 N.
Now we divide the weight of the oil by the volume of oil to find the specific weight (γ):
Specific Weight (γ) = Weight of Oil / Volume of Oil
Specific Weight (γ) = 1381 N / 179 L = 7.72 N/L (rounded to two decimal places).
The specific gravity (SG) is calculated as the ratio of the density of oil to the density of water. Since the density of water is approximately 1000 kg/m³ (which corresponds to a specific weight of approximately 9.81 N/L), the specific gravity of the oil can be found by dividing the oil's specific weight by the specific weight of water:
Specific Gravity (SG) = Specific Weight of Oil / Specific Weight of Water
Specific Gravity (SG) = 7.72 N/L / 9.81 N/L ≈ 0.79 (rounded to two decimal places).
Therefore, the correct answer is specific weight of 7.72 N/L and specific gravity of approximately 0.79, which is not exactly provided in the options, suggesting a possible typo or miscalculation in the provided choices.