An object is dropped and strikes the ground 1.9 seconds later. Ignore air resistance. To two signifcant figures, from what height was the object released? A. 150 m B. none of the above C. 75 m D. 9.8 m E. 18 m

To find the height from which the object was dropped, we can use the formula for distance under free fall: \( h = \frac{1}{2} g t^2 \), where \( g \) is the acceleration due to gravity (approximately \( 9.8 \, \text{m/s}^2 \)) and \( t \) is the time in seconds. Plugging in 1.9 seconds, we have: \( h = \frac{1}{2} \times 9.8 \times (1.9)^2 = \frac{1}{2} \times 9.8 \times 3.61 \approx 17.7 \, \text{m} \). Therefore, when rounding to two significant figures, the height is approximately 18 m. The correct answer is E. 18 m. In the world of physics, you might find that dropping objects can lead to some serious fun, especially if you have different weights or shapes to test acceleration. Next time you're outside, drop a ball and see how long it takes to hit the ground. Who knew gravity could be so entertaining? Curious about other practical applications of gravitational principles? Think about things like amusement park rides or skydiving! Understanding free fall helps engineers design thrilling rides that keep safety in mind, ensuring we can enjoy the adrenaline rush without worries.