Problema 13.1 - Mecánica Vectorial para Ingenieros - Dinámica - Beer & Johnston
Understanding Kinetic Energy in a Hybrid Vehicle Problem
Introduction to the Problem
- The problem is from "Vector Mechanics for Engineers: Dynamics" by Beer and Johnston, focusing on Chapter 13 about particle kinetics.
- It involves calculating the kinetic energy of a hybrid car weighing 1300 kg traveling at 108 km/h and determining the speed required for a truck (9000 kg) to have the same kinetic energy.
Calculating Kinetic Energy
- The formula for kinetic energy (KE) is introduced: KE = 1/2 * mass * velocity².
- The car's speed must be converted from kilometers per hour to meters per second for accurate calculations; 108 km/h converts to 30 m/s.
Step-by-Step Calculation
- For part A, the kinetic energy of the car is calculated using its mass and converted speed, resulting in KE = 585,000 Joules.
- This value can also be expressed as 585 times 10^3 Joules or Newton-meters.
Finding Truck Speed
- In part B, we need to find the truck's speed that would yield equivalent kinetic energy. The formula used is derived from rearranging KE = 1/2 * mass * velocity².
- By substituting known values into this formula, we calculate that the truck must travel at approximately 11.40 m/s to match the car's kinetic energy.
Summary of Key Steps
- Data was organized with proper unit conversions before applying formulas.