Question

In a lab investigation, a group of students measures the speed of a 0.1-kilogram car at 0.80 m/sec at the bottom of a hill. The car’s starting position at the top of the hill is one-meter high. What is the potential energy of the car at the beginning of the experiment before its speed is measured? Calculate the kinetic energy of the car using the speed and mass values above.

KE = 0.032 J

Answer 1

The potential energy at the car's starting position of one-meter height is 0.981 joules. The kinetic energy at the bottom of the hill, with a speed of 0.80 m/sec, is 0.032 joules.

Step-by-step explanation:

The student is investigating the potential energy of a car at its starting position at the top of a hill and its kinetic energy when it reaches the bottom. To calculate the potential energy (PE) at the starting position, we use the formula PE = mgh, where m is the mass of the car (0.1 kg), g is the acceleration due to gravity (9.81 m/s²), and h is the height of the hill (1 meter). Thus, PE = 0.1 kg × 9.81 m/s² × 1 m = 0.981 joules.

To calculate the kinetic energy (KE) at the bottom of the hill, we use the formula KE = 1/2 mv², where m is the mass of the car (0.1 kg) and v is its velocity (0.80 m/s). Therefore, KE = 0.5 × 0.1 kg × (0.80 m/s)² = 0.032 joules.