A wood cube 0.20m on each side has a density of 730kg/m3 and floats levelly in water.

What mass has to be placed on top of the wood so that its top is just at the water level?

See previous post: Thu,12-5-13,3:00 PM.

To find the mass that needs to be placed on top of the wood cube so that its top is just at the water level, we need to consider the buoyant force acting on the cube.

The buoyant force is the upward force exerted on an object submerged in a fluid, such as water, and is equal to the weight of the fluid displaced by the object. In this case, since the wood cube is floating levelly in water, the buoyant force acting on it is equal to its weight.

The weight of the wood cube can be calculated using the formula:

Weight = density * volume * acceleration due to gravity

Given that the density of the wood cube is 730 kg/m^3 and it has sides measuring 0.20 m, we can find its volume as:

Volume = side length^3 = (0.20 m)^3 = 0.008 m^3

Using the formula for weight, we can determine the weight of the wood cube:

Weight = 730 kg/m^3 * 0.008 m^3 * 9.8 m/s^2

Now that we have calculated the weight of the wood cube, we can determine the mass that needs to be placed on top of it. Since the buoyant force equals the weight of the cube, the mass of the extra weight can be calculated using the formula:

Mass = Weight / acceleration due to gravity

Given that the acceleration due to gravity is 9.8 m/s^2, we can calculate the mass:

Mass = Weight / 9.8 m/s^2

Therefore, the mass that needs to be placed on top of the wood cube so that its top is just at the water level is the result of this calculation.