Question

Calculate the kinetic energy of a 790-kg roller coaster traveling at a velocity of 20.7 m/s.

Answer 1

The answer is 169253.55 joules

Answer 2

`\displaystyle KE = 169254 \ J`

General Formulas and Concepts:

Energy

Kinetic Energy Formula:
`\displaystyle KE = (1)/(2)mv^2`

• KE is kinetic energy (in J)
• m is mass (in kg)
• v is velocity (in m/s)

Step-by-step explanation:

Step 1: Define

[Given] m = 790 kg

[Given] v = 20.7 m/s

Step 2: Solve

1. Substitute in variables [Kinetic Energy Formula]:
   `\displaystyle KE = (1)/(2)(790 \ kg)(20.7 \ m/s)^2`
2. [KE] Evaluate exponents:
   `\displaystyle KE = (1)/(2)(790 \ kg)(428.49 \ m^2/s^2)`
3. [KE] Multiply:
   `\displaystyle KE = (395 \ kg)(428.49 \ m^2/s^2)`
4. [KE] Multiply:
   `\displaystyle KE = 169254 \ J`