An object weighing 6000# traveling at 60 mph hits a wall. What is the force of impact ?
To determine the force of impact, you need to use Newton's second law of motion, which states that force (F) is equal to mass (m) multiplied by acceleration (a). In this case, the object is already traveling at a constant velocity of 60 mph, so the acceleration is zero. However, when the object hits the wall, it comes to a sudden stop. Thus, we can assume the acceleration is very high and occurs over a very short period of time.
To calculate the force of impact, we need to convert the mass and velocity into appropriate units.
1. Convert the weight from pounds (lbs) to mass in pounds (mass = weight / acceleration due to gravity). The acceleration due to gravity on Earth is approximately 32.2 ft/s².
mass = 6000 lbs / 32.2 ft/s² = 186.3355 slugs (1 slug is the English unit of mass)
2. Convert the velocity from miles per hour (mph) to feet per second (fps). There are 5280 feet in a mile and 3600 seconds in an hour.
velocity = 60 mph * (5280 ft / 1 mile) / (3600 s / 1 hour) = 88 fps (feet per second)
Now that we have the mass and velocity in appropriate units, we can calculate the force of impact using the equation F = m * a. Since the object comes to a sudden stop, we can assume the acceleration is very high, so let's use a rough estimate such as 100 ft/s².
F = 186.3355 slugs * 100 ft/s² = 18,633.55 lbs⋅ft/s²
The force of impact is approximately 18,633.55 pounds-force (lbsf) or 18.63 kips (kips = 1000 pounds force).