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3 years ago

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How long does it take the lava bomb to reach its maximum height? Answer with three significant digits and the correct unit. A sm

all volcano's steam pressure belches vertically upward a lava bomb from an initial height of 64.4 m and with an initial upward velocity of 31.4 m/s. Remember gravity's acceleration near earth is g = 9.8 m/s2 down.

1 answer:

wlad13 [49]3 years ago

4 0

Answer:

The time taken to reach the maximum height is 3.20 seconds

Explanation:

The given parameters are;

The initial height from which the volcano erupts the lava bomb = 64.4 m

The initial upward velocity of the lava bomb = 31.4 m/s

The acceleration due to gravity, g = 9.8 m/s²

The time it takes the lava bomb to reach its maximum height, t, is given by the following kinematic equation as follows;

v = u - g·t

Where;

v = The final velocity = 0 m/s at maximum height

u = The initial velocity = 31.4 m/s

g = The acceleration due to gravity = 9.8 m/s²

t = The time taken to reach the maximum height

Substituting the values gives;

0 = 31.4 - 9.8 × t

∴ 31.4 = 9.8 × t

t = 31.4/9.8 ≈ 3.204

The time taken to reach the maximum height rounded to three significant figures = t ≈ 3.20 seconds

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