A certain ball bearing is made of a grade of steel with a density of 4.5 ounces per cubic inch. The ball bearing is a solid sphere with a diameter of 3 inches.

What is the total weight of the ball bearing, in ounces? Use 3.14 for
.
63.585 ounces
127.17 ounces
190.755 ounces
508.68 ounces

1 answer

To calculate the total weight of the ball bearing, we first need to find its volume and then use the density to find the weight.

  1. Calculate the radius of the sphere: \[ \text{Diameter} = 3 , \text{inches} \ \text{Radius} = \frac{\text{Diameter}}{2} = \frac{3 , \text{inches}}{2} = 1.5 , \text{inches} \]

  2. Calculate the volume of the sphere using the formula for the volume of a sphere: \[ V = \frac{4}{3} \pi r^3 \] Plugging in the radius: \[ V = \frac{4}{3} \times 3.14 \times (1.5)^3 \]

    First, calculate \( (1.5)^3 \): \[ (1.5)^3 = 1.5 \times 1.5 \times 1.5 = 3.375 \]

    Now substitute back into the volume formula: \[ V = \frac{4}{3} \times 3.14 \times 3.375 = \frac{4 \times 3.14 \times 3.375}{3} \] Calculate \( 4 \times 3.14 \): \[ 4 \times 3.14 = 12.56 \] Now multiply by \( 3.375 \): \[ 12.56 \times 3.375 = 42.465 \] Now divide by 3: \[ V = \frac{42.465}{3} \approx 14.155 \] So the volume of the sphere is approximately: \[ V \approx 14.155 , \text{cubic inches} \]

  3. Calculate the weight of the ball bearing: Using the density (density = 4.5 ounces per cubic inch): \[ \text{Weight} = \text{Density} \times \text{Volume} \] \[ \text{Weight} = 4.5 , \text{oz/in}^3 \times 14.155 , \text{in}^3 \] Now, calculate the weight: \[ \text{Weight} \approx 4.5 \times 14.155 \approx 63.6975 , \text{ounces} \]

Therefore, the total weight of the ball bearing is approximately 63.7 ounces.

Among the options provided, the closest match is 63.585 ounces. Thus, the answer is:

\[ \boxed{63.585 , \text{ounces}} \]