a bullet traveling horzontally at a speed of 350m/s hits board perpendicular to its surface passes through n emerges on the other side at a speed fo 210m/s. if the board is 4.00cm thick, how long does the bullet take to pass through it.
Divide the width of the board (0.040 m) by the average speed of the bullet going through (280 m/s). This will be an approximate answer.
If the speed of the bullet varies linearly with distance, it is probably best to use an average speed Vav that is given by
1/Vav = 1/350 + 1/210
To find the time it takes for the bullet to pass through the board, we can use the equation:
time = distance / speed.
The distance the bullet travels through the board is equal to the thickness of the board. However, in order to use this equation, we need the distance in meters, as the speed is given in m/s. So, let's convert the thickness of the board from centimeters to meters.
Given:
Speed of the bullet (v) = 350 m/s
Exit speed of the bullet (v') = 210 m/s
Thickness of the board (d) = 4.00 cm = 0.04 m
Now, let's calculate the time it takes for the bullet to pass through the board:
Time = distance / speed.
The distance is the thickness of the board, which is 0.04 m.
The speed is the speed of the bullet, which is 350 m/s.
Time = 0.04 m / 350 m/s
Calculating it gives:
Time ≈ 0.000114 sec
Therefore, it takes approximately 0.000114 seconds (or 114 microseconds) for the bullet to pass through the 4.00 cm thick board.