Question

Change in acceleation per unit time is 9.81 None of them QUESTION 14 An object falls with the velocity of 7 m/s at the beginning and It hits the ground after 4.1 s. What is the initial heigh (g=9.81 m/s²

)
1, 111.15 m
2. 120.51 m
3. 82 m
4, 200.7 m

Answer 1

To solve this problem, we first need to calculate the time it takes for the object to hit the ground using the given velocity and the acceleration due to gravity. Then, we can use the equation s = (1/2)at² to find the initial height of the object.

Step-by-step explanation:

To solve this problem, we first need to calculate the time it takes for the object to hit the ground using the given velocity and the acceleration due to gravity.

Using the equation v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time, we can rearrange the equation to solve for t:

t = (v - u) / a

Plugging in the values, we have:
t = (0 - 7) / -9.81 = 0.714 s

Now, we can use the equation s = ut + (1/2)at² to find the initial height of the object. Since the object starts from rest (u = 0), the equation simplifies to:

s = (1/2)at²

Plugging in the values, we have:
s = (1/2)(-9.81)(0.714)² = 1.106 m

Therefore, the initial height of the object is approximately 1.106 meters.