You use a spring scale to suspend an object.The spring scale reads 7.84 N when the object is in air and 6.86 N when the object is immersed in water of density 1000 kg/m³.What is the density of the object? A)6000 kg/m³ B)7000 kg/m³ C)8000 kg/m³ D)9000 kg/m³

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Quizplus · Accepted Answer

The buoyant force acting on the object when it is immersed in water can be calculated by subtracting the reading of the spring scale in water (6.86 N) from the reading in air (7.84 N), which gives 0.98 N. This buoyant force is equal to the weight of the water displaced by the object, which can be used to find the volume of the object since the density of water is given (1000 kg/m^3). The volume $V$ of the object is given by $V = \frac{Force}{g \times \rho_{water}}$, where $g$ is the acceleration due to gravity (approximately 9.8 m/s^2). Once the volume is found, the density of the object ($\rho_{object}$) can be calculated using the formula $\rho_{object} = \frac{mass}{V}$, where the mass of the object can be found from its weight in air divided by $g$. Following these steps with the given numbers leads to the object's density being 8000 kg/m^3.

You Use a Spring Scale to Suspend an Object