Question

the surfing contest
make predictions · write a claim predicting what a graph of mass vs energy will look for surfers traveling at 18 km/h.
draw a mass vs energy graph. draw a line for the 18 km/h speed. add a line to show what the graph would look like if the surfers were all traveling at a speed of 12 km/h instead.

• label each line and the axis variables.
• you do not need to add a scale to your axes.

Explanation:

Step1: Recall kinetic - energy formula

The kinetic - energy formula is $E = \frac{1}{2}mv^{2}$, where $E$ is energy, $m$ is mass, and $v$ is velocity. When $v$ is constant (in this case $v = 18\ km/h$), the equation becomes $E=\frac{1}{2}v^{2}m$. Since $\frac{1}{2}v^{2}$ is a constant when $v$ is fixed, the relationship between $E$ and $m$ is a direct - proportional relationship.

Step2: Make prediction

The graph of mass ($m$) vs energy ($E$) for surfers traveling at a constant speed of $18\ km/h$ will be a straight line passing through the origin. This is because when $m = 0$, $E=0$ (from $E=\frac{1}{2}mv^{2}$), and as $m$ increases, $E$ increases linearly.

Answer:

The graph of mass vs energy for surfers traveling at 18 km/h will be a straight - line passing through the origin, indicating a direct proportional relationship between mass and energy.