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3 years ago

A cross-country skier can complete a 7. 5 km race in 45 min. What is the skier’s average speed? km/h.

Physics

1 answer:

never [62]3 years ago

8 0

The average speed is a scalar quantity. The average speed of the skier is 10 km/hrs.

<h3>What is the average speed?</h3>

It is calculated by dividing the total distance by the total time elapsed.

The

$\overline{v}={\frac{\Delta x}{\Delta t}}$

Where,

$\overline{v}$ = average velocity

${\Delta x}$ = displacement = 7.5 km

${\Delta t}$ = change in time = 45 min = 0.75 hours

Put the values in the formula,

$\overline{v}={\frac{7.5 }{0.75 }}\\\\\overline{v}= 10 \rm \ km/hrs$

Therefore, the average speed of the skier is 10 km/hrs.

Learn more about average speed:

https://brainly.in/question/32459982

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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.

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4 years ago

How does the current model of the atom differ from<br> j j thomas model

bixtya [17]

Jj thomas' model contained electrons.

The current model contains a nucleus with electrons orbiting around it. :)

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3 years ago

67 points plus brainlest if done correctly.I will report you if you answer 3 or less of the questions, also must post all the an

Annette [7]

im sorry but i dont know, good luck at finding someone else who does.

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3 years ago

You are exploring a distant planet. When your spaceship is in a circular orbit at a distance of 630 km above the planet's surfac

Anarel [89]

Answer:

$R = 24.3 m$

Explanation:

As we know that the orbital speed is given as

$v = \sqrt{\frac{GM}{R + h}}$

here we know that

v = 5500 m/s

$R = 4.48 \times 10^6 m$

$h = 630 km$

now we have

$5500 = \sqrt{\frac{(6.6 \times 10^{-11})M}{4.48 \times 10^6 + 6.30\times 10^5}}$

$M = 2.34 \times 10^24 kg$

now acceleration due to gravity of planet is given as

$a = \frac{GM}{R^2}$

$a = \frac{(6.6 \times 10^{-11})(2.34 \times 10^{24})}{(4.48\times 10^6)^2}$

$a = 7.7 m/s^2$

now range of the projectile on the surface of planet is given as

$R = \frac{v^2 sin2\theta}{g}$

$R = \frac{14.6^2 sin(2\times 30.8)}{7.7}$

$R = 24.3 m$

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4 years ago

A small bug walks up a wall 2 m. The bug then walks 2 m down the wall. What is the distance?

gizmo_the_mogwai [7]

4m. The big travels 2m twice

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2 years ago

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