A cubes weight 15N in air and 20N when totally immersed in water. Find the value of the cube of the density. Please I need the answer.
the given data is unrealistic
please check it
Hmmm. You put it in water, submerge it, and it weighs more? That means the bouyance force is negative, sucking the cube down. Most unusual
To find the value of the cube's density, we can use the concept of buoyancy.
The buoyant force acting on an object submerged in a fluid is equal to the weight of the fluid displaced by the object. When the cube is immersed in water, it displaces a certain amount of water, and the buoyant force acting on it is equal to the weight of this displaced water.
In this case, the weight of the cube in air is 15N, and the weight of the cube when submerged in water is 20N. The difference between these two weights (20N - 15N = 5N) is equal to the weight of the displaced water.
Now, we can use this information to find the density of water and, subsequently, the density of the cube.
The density of water is approximately 1000 kg/m³. We need to convert the weight of the displaced water (5N) to kilograms.
We know that weight (W) is equal to mass (m) multiplied by the acceleration due to gravity (g). The formula is W = m * g.
Rearranging the formula to solve for mass, we get m = W / g.
Considering the weight of water is equivalent to the mass of water multiplied by the acceleration due to gravity, the weight of the displaced water is the mass of the displaced water multiplied by the acceleration due to gravity. So we have:
Weight of displaced water = mass of displaced water * g
Substituting the values, 5N = (mass of displaced water) * 9.8 m/s².
To find the density of the cube, we need the volume of the cube. Since it's a cube, the volume is given by V = s³, where s is the side length of the cube.
Now, let's substitute the equation for mass into the formula for density. Density (ρ) is equal to mass (m) divided by volume (V). So we have:
ρ = m / V.
Substituting the value of mass as the weight of the displaced water divided by the acceleration due to gravity, we get:
ρ = (Weight of displaced water / g) / V.
Finally, we substitute the weight of the displaced water as 5N, the acceleration due to gravity as 9.8 m/s², and calculate the value of the volume of the cube using the formula V = s³.
By substituting all these values and performing the calculations, we can find the value of the cube's density.