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ahrayia [7]
3 years ago
10

A rifle with a barrel length of 60 cm fires a 10 g bullet with a horizontal speed of 400 m/s. The bullet strikes a block of wood

and penetrates to a depth of 12 cm. . a. what resistive force (assumed to be constant) does the wood exert on the bullet? . b. How long does it take the bullet to come to rest? . c. Draw a velocity verses time graph for the bullet in the wood.

Physics
2 answers:
antoniya [11.8K]3 years ago
8 0

consider the motion of bullet as it penetrates through the block

v₀ = initial velocity of the bullet  = 400 m/s

v = final velocity of the bullet  = 0 m/s

d = distance traveled = 12 cm = 0.12 m

a = acceleration = ?

Using the equation

v² = v₀² + 2 a d

0² = 400² + 2a (0.12)

a = - 6.67 x 10⁵ m/s²

m = mass of the bullet = 10 g = 0.010 kg

The resistive force is given as

f = ma

inserting the values

f = (0.010) (- 6.67 x 10⁵ )

f = - 6670 N

b)

t = time taken by the bullet

using the equation

v = v₀ + a t

0 = 400 + (- 6.67 x 10⁵ ) t

t = 6 x 10⁻⁴ sec

c)

Sholpan [36]3 years ago
6 0
  bullet's change in kinetic energy=<span>   The work done by the resistive force "F" </span>

<span>-Fx = 0 - (1/2)mv^2 </span>

<span>F(.12) = (1/2)(.01)(160000) </span>

<span>F = 6666.7 N </span>
<span>change in momentum; </span>


<span>- (6666.7)t = 0 - (.01)(400) </span>

<span>t = .0006 s </span>

<span>the bullets acceleration is </span>

<span>a = - F/m = - 666667 m/s2 </span>

<span>So plot the graph; </span>

v = 400 - (666667)t
hope this helps
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Explanation:

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We need to find its heat of vaporization. It can be calculated by using Clausius-Clapeyron equation.

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\Delta _{vap} H=\dfrac{R\ ln(\dfrac{P_2}{P_1})}{(\dfrac{1}{T_1}-\dfrac{1}{T_2})}

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So, the heat of vaporization of a substance is 29.31 kJ/mol. Hence, this is the required solution.

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3 years ago
The index of refraction of a clear plastic is listed as 1.89 in the book, but you measured the angle of incidence 63.5° and the
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Answer:

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Answer:

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Explanation:

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The spring constant k can be found by

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<h3><u>Answer;</u></h3>

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7 0
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