A 6.8 g bullet travelling at 395m/s goes through a stationary block of wood in 4.3 *10^-4 and emerges at 102 m/s.
what average force did the wood exert on the bullet ?
how thick is the wood?
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To find the average force exerted by the wood on the bullet, you can use the principle of impulse-momentum. The impulse experienced by the bullet is equal to the change in momentum. The formula for impulse is given by:
Impulse = Change in momentum = Final momentum - Initial momentum
We can calculate the initial momentum of the bullet using the mass and initial velocity:
Initial momentum = Mass x Initial velocity
Since the bullet is initially at rest (stationary block), the initial velocity is 0. Therefore, the initial momentum is 0.
The final momentum of the bullet can be calculated using the mass and final velocity:
Final momentum = Mass x Final velocity
The change in momentum is the difference between the final and initial momentum:
Change in momentum = Final momentum - Initial momentum = Mass x Final velocity
The average force can be calculated using the formula:
Average force = Change in momentum / Time
Given:
Mass of the bullet (m) = 6.8 g = 0.0068 kg
Initial velocity = 0 m/s
Final velocity = 102 m/s
Time = 4.3 * 10^-4 s
Calculating the final momentum:
Final momentum = Mass x Final velocity = 0.0068 kg x 102 m/s
Next, calculate the change in momentum:
Change in momentum = Final momentum - Initial momentum = 0.0068 kg x 102 m/s
Finally, calculate the average force:
Average force = Change in momentum / Time = (0.0068 kg x 102 m/s) / (4.3 * 10^-4 s)
Now, let's proceed to calculate the average force:
Average force = (0.0068 kg x 102 m/s) / (4.3 * 10^-4 s)
To find the thickness of the wood, we need to determine the distance the bullet traveled through the wood. The distance traveled through the wood can be calculated using the equation:
Distance = Initial velocity x Time + (1/2) x Acceleration x Time^2
Since the bullet is initially at rest (stationary block), the initial velocity is 0. Therefore, the equation simplifies to:
Distance = (1/2) x Acceleration x Time^2
However, we need to determine the acceleration of the bullet while going through the wood. Unfortunately, the information provided doesn't allow us to determine the acceleration, so we cannot find the thickness of the wood with the given data.