Question

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

Answer 1

Answer:

$\displaystyle KE = 169254 \ J$

General Formulas and Concepts:

Energy

Kinetic Energy Formula: $\displaystyle KE = \frac{1}{2}mv^2$

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

Explanation:

Step 1: Define

[Given] m = 790 kg

[Given] v = 20.7 m/s

Step 2: Solve

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

Answer 2

Answer:

The answer is 169253.55 joules