Reflection and What if Questions!
1. Given the balls of different mass which ball do you think was traveling the
fastest (the lighter one or the heavier one). Remember the relationship
between energy, velocity and mass for potential and kinetic energy. (hint:
more kinetic energy means more velocity).
The heavier ball was traveling faster than the lighter ball. In timing the balls, it
took the heavier ball 3.27 seconds and the lighter ball 3.45 seconds to get to the
to cup from the moment we let it go at the beginning of the rollercoaster. The
average velocity of the heavier ball was 199.99 inches/second and the lighter ball
had a velocity of 179.13 inches/second. Therefore, the heavier ball was clearly
faster. Kinetic energy is defined as the energy of motion. The formula for kinetic
energy is KE=0.5 mass * velocity2. The formula implies that a small change in
speed causes a large change in Kinetic Energy and therefore the lighter ball has
a lot less kinetic energy. Furthermore, more mass means more kinetic energy.
On the other hand, potential energy depends on mass and height and more
mass implies more potential energy.
2. Imagine that you could double the initial height of the first hill of your roller
coaster. What would happen to the speed of the ball?
Potential Energy is defined the energy of position, in other words, energy that is
stored and held in readiness. Gravitational Potential Energy is basically the
potential energy of an object thanks to the height it is positioned at. This is due to
the gravity. Gravitational Potential Energy equals weight or mass of the object *
height. Therefore, if the first hill of our roller coaster would be higher, the
gravitational potential energy would be a lot higher and the ball would get faster
and faster as it accelerated. Furthermore, while the ball is falling, the height gets
smaller and smaller and therefore the ball loses potential energy and gains
kinetic energy. It is important to note that energy is not created or destroyed, it is
simply transformed and the loss of potential energy simply means that this
energy will be transformed into another one. When the hill is higher, the impact of
the ball against the bottom of it is stronger because the velocity was very high
and potential energy is therefore lost an