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2 years ago

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a bullet fired straight through a board 0.10 mm thick strikes the board with a speed of 480 m/sm/s, has constant acceleration th

rough the board, and emerges with a speed of 345 m/sm/s.

1 answer:

vekshin12 years ago

5 0

the average acceleration of the bullet through the board -55657×10⁵ m/s²

acceleration- Rate of change of velocity with respect to time.

S = 0.10 mm = 10⁻⁵ m ( distance) [∵ 1mm = 10⁻³]

u = 480 m/s (initial velocity)

v = 345 m/s (final velocity)

As we know the 3rd equation of motion.

v² = u² + 2aS

a = ? ( acceleration)

using these values in equation we get

(345)² = (480)² + 2×a× 10⁻⁵

a = (345)² - (480)² / 2× 10⁻⁵

a = -55657×10⁵ m/s²

The negative sign shows that the direction of acceleration is opposite of velocity thus bullet is slowing down.

the average acceleration of the bullet through the board -55657×10⁵ m/s²

The given question is incomplete. The complete question is.

a bullet fired straight through a board 0.10 mm thick strikes the board with a speed of 480 m/sm/s, has constant acceleration through the board, and emerges with a speed of 345 m/sm/s.

What is the average acceleration of the bullet through the board/?

to know more about the equation of motion :

brainly.com/question/13269040

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