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3 years ago

5

A column of soldiers, marching at 121 steps per minute, keep in step with the beat of a drummer at the head of the column. It is

observed that the soldiers in the rear end of the column are striding forward with the left foot when the drummer is advancing with the right. What is the approximate length of the column? (Take the speed of sound to be 343 m/s.)

1 answer:

Novay_Z [31]3 years ago

7 0

There’s a first “clump”/drum beat every half second. That clump will travel about 170m in half a second. Someone 170m away would do their “clump” as the second “clump” was taking place. I think. <span> </span>

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Answer:

Kinetic energy doubles

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He shoots the tree stump, which has a mass of (M), with a bullet of mass (m) traveling at some velocity (vbullet), and the bulle

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Answer:

Explanation:

Given

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3 years ago

Suppose the rocket in the Example was initially on a circular orbit around Earth with a period of 1.6 days. Hint (a) What is its

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a

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b

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Where T is the period which is given as 1.6 days = $1.6 *24 *60*60 = 138240 sec$

Substituting the value

$w = \frac{2 \pi}{138240}$

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r is the distance between earth and circular orbit where the rocke is found

Making r the subject

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$v= (5.78*10^7)(4.54*10^{-5})$

$v= 2.6*10^{3} m/s$

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$v_e = \sqrt{\frac{2GM}{r} }$

Substituting values

$= \sqrt{\frac{2(6.67*10^{-11})(5.98*10^{24})}{5.78*10^7} }$

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3 years ago

If the particle has mass m, how fast must it be moving away from the Sun's center of mass to escape the gravitational influence

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Answer:

Explanation:

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