A 2.15 kg book is dropped from a height of

Question

A 2.15 kg book is dropped from a height of

1.8 m.
a) What is its acceleration?
Answer in units of m/s2.

Answer 1

anything falling has the acceleration due to gravity, 9.8m/s^2

Answer 2

i tried that i don't know why its not right

Answer 3

i put -9.8m/s^2

it worked:)

Answer 4

To calculate the acceleration, we can use the equation of motion:

𝑠 = 𝑢𝑡 + 0.5𝑎𝑡^2

Where:
𝑠 = distance (in this case, the height) = 1.8 m
𝑢 = initial velocity = 0 m/s (as the book is dropped)
𝑡 = time taken to fall
𝑎 = acceleration (what we need to find)

Since the book is only falling vertically under the force of gravity, we can use the equation for gravitational acceleration:

𝑎 = 𝑔 ≈ 9.8 m/s^2

Substitute the given values into the equation of motion:

1.8 = 0.5 * 9.8 * 𝑡^2

To solve for 𝑡^2, we can rearrange the equation:

0.5 * 9.8 * 𝑡^2 = 1.8

Multiply both sides by 2:
9.8 * 𝑡^2 = 3.6

Divide both sides by 9.8:
𝑡^2 = 3.6 / 9.8

Take the square root of both sides to solve for 𝑡:
𝑡 = √(3.6 / 9.8)

𝑡 ≈ 0.6709 s

Now that we have the time, we can substitute it back into the equation of motion to find the acceleration:

𝑎 = (𝑠 - 𝑢𝑡) / (0.5𝑡^2)

𝑎 = (1.8 - 0) / (0.5 * 0.6709^2)

𝑎 ≈ 5.42 m/s^2

So, the acceleration of the book is approximately 5.42 m/s^2.