Cast iron block weighing 700 g is completely submerged in gasoline. Determine the weight of this block in gasoline.

To find out the weight of the specified cast-iron bar in gasoline, use the formula: Pb = Pair – FA = mb * g – ρb * g * V = mb * g – ρb * g * mb / ρh = (1 – ρb / ρh) * mb * g.

Const: ρb – gasoline density (according to the condition ρb = 710 kg / m3); ρch – density of cast iron (according to the condition ρh = 7000 kg / m3); g – acceleration due to gravity (g ≈ 9.81 m / s2).

Data: mb – the mass of the specified cast-iron bar (mb = 700 g; in SI mb = 0.7 kg).

Let us perform the calculation: Pb = (1 – ρb / ρh) * mb * g = (1 – 710/7000) * 0.7 * 9.81 ≈ 6.17 N.

Answer: The weight of the specified cast-iron bar in gasoline, according to the calculation, is 6.17 N.