Question

2 formula 1 point what is the mass of a car that has 1,278,368 j of ke and is travelling at 90 m/s? report your answer to 3 decimal places. your permitted error is ±0.001 j. answer

Explanation:

Step1: Write the kinetic energy formula

The formula for kinetic energy \(KE=\frac{1}{2}mv^{2}\), where \(KE\) is kinetic energy, \(m\) is mass, and \(v\) is velocity. We need to solve for \(m\). Rearranging the formula gives \(m = \frac{2KE}{v^{2}}\).

Step2: Substitute the given values

Given \(KE = 1278368\space J\) and \(v=90\space m/s\). Substitute into the formula: \(m=\frac{2\times1278368}{90^{2}}\).
First, calculate \(90^{2}=8100\). Then \(2\times1278368 = 2556736\).
So \(m=\frac{2556736}{8100}\).

Step3: Perform the division

\(m=\frac{2556736}{8100}=315.64641975\approx315.646\) (rounded to 3 decimal places)

Answer:

\(315.646\)