The impact of a crash at 60 mph is equal to that of a fall off a __ building.
Answers
5-story
8-story
10-story
The Correct Answer and Explanation is :
The correct answer is 10-story building.
To understand why, let’s break down the physics involved in both the crash and the fall. The impact of a crash at 60 mph (miles per hour) and the impact of falling from a building are both examples of high-speed, high-energy events that cause injury or damage.
Crash at 60 mph:
A crash at 60 mph involves a car traveling at high speed, and upon collision, the car rapidly decelerates. The body inside the vehicle experiences a sudden stop, with the forces of impact potentially causing severe injury depending on the nature of the crash and safety features like airbags and seat belts. The speed of 60 mph is roughly 88 feet per second, which means a car traveling at that speed will cover the length of a football field (approximately 300 feet) in about 3.4 seconds.
Fall from a Building:
A fall from a height involves gravity accelerating a person towards the ground. The speed at which a person reaches the ground depends on the height from which they fall. On average, a person will accelerate at about 32 feet per second² due to gravity. The speed of impact from a fall can be estimated using the formula for velocity in free fall:
[
v = \sqrt{2gh}
]
Where:
- (v) is the final velocity upon impact,
- (g) is the acceleration due to gravity (32 ft/s²),
- (h) is the height in feet.
A fall from a 10-story building (roughly 100 feet tall) results in an impact velocity of about 60 mph. This is the same as the speed at which a car is traveling in the crash scenario.
Therefore, the impact from a 10-story building fall is roughly equal to the impact of a crash at 60 mph. This comparison helps highlight how dangerous high-speed impacts, whether from a crash or a fall, can be.