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3 years ago

A race car circles 10 times around a circular 8.0-km track in 20 min.

2 answers:

6 0

Find the average speed and the average velocity.

Average speed = distance / time

distance = 10 x 8000 m = 80,000 m
time = 20 min * 60 s/min = 1200 s

Average speed = 80,000 m / 1200 s = 66.67 m/s

Average velocity = displacement / time

Given that the race car made complete circles the final poin is the same initial point, then its displacement is zero and the average velocity is zero too.

fredd [130]3 years ago

5 0

Assuming that you're asking for the average speed,

Average speed = distance / time

since he circle 8 km track 10 times, the distance is 80,000 m and the time is 20 min or 1200 seconds
Average speed = 80,000 / 1200 = 66.67 m/s

Hope this helps

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Answer:

r=x+y

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3 years ago

What is the order of magnitude of the distance of Sun to nearest star in meters?

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Answer:

Approximating the Milky Way as a disk and using the density in the solar neighborhood, there are about 100 billion stars in the Milky Way.

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2 years ago

Read 2 more answers

Movies and TV shows sometimes portray a person being thrown backwards a sizable distance as a result of being struck by a bullet

MAXImum [283]

Answer:

R = 4.24 x 10⁻⁴ m

Explanation:

given,

mass of the person = 60.3-kg

mass of the bullet = 10 gram = 0.01 Kg

velocity of bullet = 389 m/s

angle made with the horizontal = 45°

using conservation of momentum.

M v + m u = ( M + m ) V

60.3 x 0 + 0.01 x 389 = (60.3 + 0.01) V

$V = \dfrac{3.89}{60.31}$

V = 0.0645 m/s

for calculation of range

$R = \dfrac{V^2sin 2 \theta}{g}$

$R = \dfrac{0.0645^2sin 2 (45^0)}{9.8}$

R = 4.24 x 10⁻⁴ m

the distance actor fall is R = 4.24 x 10⁻⁴ m

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3 years ago

1. On this graph, what is the change in velocity between 5 seconds and 8 seconds?

alukav5142 [94]

Can I see the graph so I can help you

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2 years ago

A car is moving in uniform circular motion. If the cars speed were to double to keep the car moving with the same radius the acc

Stells [14]

Answer:

The centripetal acceleration would increase by a factor of 4

Correct choice: B.

Explanation:

Circular Motion

The circular motion is described when an object rotates about a fixed point called center. The distance from the object to the center is the radius. There are other magnitudes in the circular motion like the angular speed, tangent speed, and centripetal acceleration. The formulas are:

$v_t=w\ r$

$\displaystyle a_c=\frac{v_t^2}{r}$

If the speed is doubled and the radius is the same, then

$\displaystyle a_c=\frac{(2v_t)^2}{r}$

$\displaystyle a_c=4\frac{v_t^2}{r}$

The centripetal acceleration would increase by a factor of 4

Correct choice: B.

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3 years ago