Question

A penny is dropped from the top of a very deep well. If the penny started from rest and it took 40 seconds for the penny to hit the bottom of the well, how deep is the well?

A. 400 m
B. 392 m
C. 784 m
D. 196 m.

Answer 1

Using the formula for free fall motion, d = (1/2)gt², with g = 9.8 m/s² and t = 40 seconds, the depth of the well is calculated to be 7840 m, indicating a hypothetical scenario. so, option C is the correct answer.

Step-by-step explanation:

To solve for the depth of the well in the student's question on how deep is the well when a penny is dropped from the top and takes 40 seconds to hit the bottom, we use the formula of free fall motion which is d = (1/2)gt², where d is the distance, g is the acceleration due to gravity (approximately 9.8 m/s²), and t is the time it takes for the object to fall. Substituting the given values, we have d = (1/2)(9.8 m/s²)(40 s)². After computing the values, we find that the depth of the well is 7840 m (which appears to be a very unrealistic depth for a well and indicates that the problem is likely hypothetical or that the time given is not accurate for a real-life scenario).

To calculate the depth of the well, we can use the equation for free fall motion: d = 1/2 * g * t^2, where d is the depth of the well, g is the acceleration due to gravity (approximately 9.8 m/s^2), and t is the time it takes for the penny to hit the bottom.

Plugging in the values, we get: d = 1/2 * 9.8 * (40)^2 = 784 meters.

Therefore, the depth of the well is 784 meters.