Question

what is the kinetic energy of a 1,159 kg car going at a speed of 4.9 meters per second?
report your answer to 1 decimal place. your permitted error is ±0.1 j. if your answer is negative, please make sure to include the negative sign.

Explanation:

Step1: Write the formula for kinetic energy

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

Step2: Substitute the given values

Given \( m = 1159\space kg \) and \( v=4.9\space m/s \). Substitute into the formula: \( KE=\frac{1}{2}\times1159\times(4.9)^{2} \).
First calculate \( (4.9)^{2}=24.01 \). Then \( \frac{1}{2}\times1159\times24.01 = 579.5\times24.01 \).

Step3: Perform the multiplication

\( 579.5\times24.01=(500 + 79.5)\times24.01=500\times24.01+79.5\times24.01 \).
\( 500\times24.01 = 12005 \), \( 79.5\times24.01=(80 - 0.5)\times24.01=80\times24.01-0.5\times24.01=1920.8 - 12.005 = 1908.795 \).
\( 12005+1908.795=13913.795\approx13913.8\) (rounded to one decimal place)

Answer:

\(13913.8\)