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3 years ago

13

Suppose a vacuum cleaner uses 120 J of electrical energy. If 45 J are used to pull air into the vacuum cleaner, how efficient is

the vacuum cleaner?

1 answer:

Zigmanuir [339]3 years ago

3 0

Efficiency = 45J/120J = 0.375

Or

0.375 * 100% = 37.5 %

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Answer:

Typically found in eukaryotic cells, centrioles are cylindrical (tube-like) structures/organelles composed of microtubules. In the cell, centrioles aid in cell division by facilitating the separation of chromosomes. For this reason, they are located near the nucleus.

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Rick shoots a basketball at an angle of 35' from the horizontal. It leaves his hands 7 feet from the ground with a velocity of 2

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Given:

The angle of projection of the basketball, θ=35°

The height at which the ball leaves the hand, h=7 ft

The initial velocity of the basketball, v=20 ft/s

To find:

The parametric equations describing the shot.

Explanation:

The range, x of the basketball is given by,

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On substituting the known values,

$\begin{gathered} x=20\times\cos35\degree\times t \\ \implies x=16.4t \end{gathered}$

The change in the height, y of the basketball is given by,

$y=-v\sin\theta t+\frac{1}{2}gt^2$

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On substituting the known values,

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Final answer:

The parametric equations describing the shot are

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1 year ago

You pull a block of mass m across across a frictionless table with a constant force. you also pull with an equal constant force

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For any mass m:

a = F/m
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Explanation:

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Explanation:

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Hope this helps!

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