Question

A bullet is fired through a board, 14.0 cm thick, with its line of motion perpendicular to the face of the board. if it enters with a speed of 450 m/s and emerges with a speed of 220 m/s, what is the bullet's acceleration as it passes through the board?

Answer 1

Answer:

$a = -5.66 \times 10^5 m/s^2$

Explanation:

Here we know

initial speed will be

$v_i = 450 m/s$

final speed is

$v_f = 220 m/s$

total distance moved through it is given as

$d = 14 cm$

now we will use kinematics to find the acceleration

$v_f^2 - v_i^2 = 2 a d$

$220^2 - 450^2 = 2(a)(0.14)$

$a = -5.66 \times 10^5 m/s^2$

Answer 2

The acceleration of a bullet that is fired through a board of 14.0 cm thick, with an initial and final speed of 450 m/s and 220 m/s, respectively, is -5.50x10⁵ m/s².  

The acceleration of the bullet can be calculated with the following equation:

$v_{f}^{2} = v_{i}^{2} + 2ad$   (1)

Where:

$v_{f}$: is the final speed = 220 m/s

$v_{i}$: is the initial speed = 450 m/s

a: is the acceleration =?

d: is the distance = 14.0 cm = 0.14 m

Hence, by solving equation (1) for a, we have:

$a = \frac{v_{f}^{2} - v_{i}^{2}}{2d} = \frac{(220 m/s)^{2} - (450 m/s)^{2}}{2*0.14 m} = -5.50 \cdot 10^{5} m/s^{2}$

The minus sign is because the bullet decelerates as it passes through the board.  

Therefore, the bullet's acceleration as it passes through the board is -5.50x10⁵ m/s².

       

To learn more about negative acceleration, go here: https://brainly.com/question/8404138?referrer=searchResults

I hope it helps you!