As shown below, a student places a 500-gram car at point X on a wooden racetrack in an energy transformation investigation.

Question

What outcome is most likely if the student uses a 700-gram car instead?

(1 point)
Responses

A 700-gram car would have more potential energy at point X and more kinetic energy at the bottom of the racetrack
A 700-gram car would have more potential energy at point X and more kinetic energy at the bottom of the racetrack

A 700-gram car would have more kinetic energy at point X and less potential energy at the bottom of the racetrack
A 700-gram car would have more kinetic energy at point X and less potential energy at the bottom of the racetrack

A 700-gram car would have less kinetic energy at point X and less potential energy at the bottom of the racetrack
A 700-gram car would have less kinetic energy at point X and less potential energy at the bottom of the racetrack

A 700-gram car would have less potential energy at point X and less kinetic energy at the bottom of the racetrack
A 700-gram car would have less potential energy at point X and less kinetic energy at the bottom of the racetrack

Answer 1

To determine the outcome, we need to consider the concepts of potential energy and kinetic energy.

1. Potential Energy (PE) is given by the formula:
   \[ PE = mgh \]
   where
   \( m \) = mass (in kilograms),
   \( g \) = acceleration due to gravity (approximately \( 9.81 , m/s^2 \)),
   \( h \) = height (in meters).

2. Kinetic Energy (KE) is given by the formula:
   \[ KE = \frac{1}{2} mv^2 \]
   where
   \( m \) = mass (in kilograms),
   \( v \) = velocity (in meters per second).

In this situation, if the 700-gram car (which is 0.7 kg) is placed at point X, it will have more mass than the 500-gram car (0.5 kg). Thus, the potential energy at point X will be greater for the 700-gram car if they are raised to the same height.

When the car moves down the racetrack, the potential energy will convert to kinetic energy. Therefore, a 700-gram car will have more potential energy at point X compared to the 500-gram car, leading to more kinetic energy at the bottom of the racetrack as well.

Thus, the correct response is:

A 700-gram car would have more potential energy at point X and more kinetic energy at the bottom of the racetrack.