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3 years ago

10

A bullet in a gun is accelerated from the firing chamber to the end of the barrel at an average rate of 6.20×105m/s2 for 8.10×10

-4s. What is its muzzle velocity (that is, its final velocity)?

1 answer:

kati45 [8]3 years ago

7 0

Answer:

502.2 m/s

Explanation:

initial velocity, u = 0 m/s

Let the final speed is v.

acceleration, a = 6.2 x 10^5 m/s^2

time taken, t = 8.10 x 10^-4 s

The muzzle speed is the final speed.

Use first equation of motion

v = u + a t

v = 0 + 6.2 x 10^5 x 8.10 x 10^-4

v = 502.2 m/s

Thus, the muzzle speed of the bullet is 502.2 m/s.

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Mass and weight are very different concepts.

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<h2>Answer 2: b. Force changes by 2/9</h2>

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If we compare (1) and (2) we will be able to see the force changes by 2/9.

<h2>Answer 3: b. movement</h2>

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<h2>Answer 5: c. the soil will be 5°C</h2>

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$Q=m. c. \Delta T$ (12)

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