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2 years ago

A boy flies a kite with the string at a 30 degree angle to the horizontal. The tension in the string is 4.5N .

1 answer:

8 0

From our physics class, we know that Work is a product of Force and Displacement. The force must be the force in the same direction with the displacement. So force and displacement must be parallel.

A. How much work in J does the string do on the boy if the boy stands still?

Since we know that: Work = Force * Displacement

and in this case displacement is equal to zero, therefore Work must also be equal to zero.

Work = 0

B. How much work does the string do on the boy if the boy walks a horizontal distance of 11m away from the kite?

Now are given a displacement of 11 m which is a horizontal distance. Therefore we must first calculate the horizontal component of force:

Fx = 4.5 N * cos 30

Fx = 3.897 N

So work is:

Work = 3.897 N * 11 m

Work = 42.87 J ~ 43 J

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During which phase of mitosis do the chromosomes line up across the center of the cell?

nirvana33 [79]

Metaphase; the centromeres of duplicated chromosomes line up in the middle of the cell. (It's also the shortest phase of mitosis).

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3 years ago

Jupiter's gravitational field is stronger than Earth's. On Jupiter, an object's__________ will be greater than on Earth. What on

vesna_86 [32]

Answer: Weight

Explanation:The mass of an object is a measure of the quantity of matter in the object. This quantity remains constant under any circumstance.

However, the same cannot be said about the weight of such object.

The weight of the object is very much dependent on the acceleration due to gravity which is a accelerational pull (by convention-- a pull downwards).

This is why an object tends to fall when it is thrown upwards on the earth for instance.

The statements above consequently infer that since the gravitational field of Jupiter is greater than that of the earth, the acceleration due to gravity on Jupiter is greater than that on earth.

And since the weight of an object(W) is a product of its mass and the acceleration due to gravity at that point.

Consequently, the object's weight on Jupiter would be greater than its weight on earth.

Please note; The Mass of the object remains constant everywhere.

3 0

3 years ago

How many grams are in 6.53 moles of Mn?

Westkost [7]

Answer:

359 g Mn

General Formulas and Concepts:

Dimensional Analysis
Reading the Periodic Table of Elements

Explanation:

Step 1: Define

6.53 mol Mn

Step 2: Find conversion

1 mol Mn = 54.94 g Mn

Step 3: Dimensional Analysis

$6.53 \hspace{3} mol \hspace{3} Mn(\frac{54.94 \hspace{3} g \hspace{3} Mn}{1 \hspace{3} mol \hspace{3} Mn} )$ = 358.758 g Mn

Step 4: Simplify

We are given 3 sig figs.

358.758 g Mn ≈ 359 g Mn

3 0

2 years ago

Which of the following statements are true?

inessss [21]

Answer:

a. If an object's speed is constant, then its acceleration must be zero.

FALSE

As we know that acceleration is defined as the rate of change in velocity

$a = \frac{d\vec v}{dt}$

so we can not say anything about the acceleration when speed is given to as and no information is given about velocity

b. If an object's acceleration is zero, then its speed must be constant.

TRUE

As we know that acceleration is defined as the rate of change in velocity

$a = \frac{d\vec v}{dt}$

Since we know that if acceleration is 0 then velocity must be constant and hence speed is also constant

c. If an object's velocity is constant, then its speed must be constant.

TRUE

Since velocity is constant then it shows that its magnitude and direction both are constant so its speed is also constant.

d. If an object's acceleration is zero, its velocity must be constant.

TRUE

As we know that acceleration is defined as the rate of change in velocity

$a = \frac{d\vec v}{dt}$

Since we know that if acceleration is 0 then velocity must be constant

e. If an object's speed is constant, then its velocity must be constant.

FALSE

Speed is just the magnitude so we can not say about its direction and hence if speed is constant then velocity may or may not change

7 0

2 years ago

Please help !! In the diagram, q1 = +0.00200 C, q2 = 0.00180 C, and q3 = +0.00830 C. the net force on q2 is zero. how far is q2

VikaD [51]

Answer:

2.03715

Explanation:

$32364=8.99\cdot 10^9\cdot \frac{0.00180\cdot 0.00830}{2.03715^2}$

4 0

3 years ago