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2 years ago

Please help me with this question guys.

Physics

1 answer:

katen-ka-za [31]2 years ago

7 0

Answer:

<em>The average speed is 22.2 km/h</em>

Explanation:

<u>Average Speed</u>

Given an object travels a total distance d and took a total time t, then the average speed is:

$\displaystyle \bar v=\frac{d}{t}$

The mailman first drives d1=7 km at v1=15 km/h. The time taken to drive is:

$\displaystyle t1=\frac{d1}{v1}=\frac{7}{15}=0.467\ h$

Then he drives d2=7 km at v2=43 km/h taking a time of:

$\displaystyle t2=\frac{d2}{v2}=\frac{7}{43}=0.163\ h$

The total time is

t=0.467 h + 0.163 h = 0.63 h

The total distance is

d = 7 km + 7 km = 14 km

The average speed is:

$\displaystyle \bar v=\frac{14}{0.63}=22.2\ km/h$

The average speed is 22.2 km/h

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What type of tissue in the heart pumps blood throughout the body?

slavikrds [6]

Answer:

Myocardium. That is the type. (srry i was in a rush hope this helps)

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2 years ago

The basic barometer can be used to measure the height of a building. If the barometric readings at the top and the bottom of a b

erma4kov [3.2K]

Answer:

$h = 269.6 m$

Explanation:

Pressure at the bottom of the building and at the top of the building must be related as

$P_{top} = P_{bottom} - \rho g h$

$P_{top} = 730 mm Hg$

$P_{bottom} = 755 mm Hg$

now we will have

$(755 \times 10^{-3})(13.6 \times 10^3)(9.81) = P_{bottom}$

$P_{bottom} = 1.007 \times 10^5 Pa$

$P_{top} = (730\times 10^{-3})(13.6 \times 10^3)(9.81)$

$P_{top} = 0.974 \times 10^5$

now we have

$(1.007 - 0.974)\times 10^5 = 1.25 (9.81) h$

$h = 269.6 m$

7 0

3 years ago

IBM has a fast computer that it calls the Blue Gene/L that can do '136.8

dmitriy555 [2]

Answer:

138.6 megacalculations

Explanation:

This is a pretty straightforward one.

All it needs is to convert the degree of measurement.

Dimensions in physics are attributed names, which state the power to which they're are raised. Just as how

Kilo and Mega means the numbers are raised to the power of 3 and 6 respectively. There also exists the ones that indicates how small, such as milli and micro, which are to the powers of -3 & -6.

The question says the IBM computer calculates at an astonishing 136.8 teracalculations.

Tera in physics means it's raised to the power of 12. Thus, the IBM calculates at an astonishing rate of

136.8*10^12 calculations per second.

We're then asked how many calculations it does in 1 micro second. Like I had highlighted earlier, 1 micro second is 1 raised to the power of -6. Or succinctly put,

1 micro second = 1*10^-6.

If the IBM does

138.6*10^12 = 1 second,

Then it does

x = 1*10^-6 second.

When we cross multiply, we have

138.6*10^12 * 1*10^-6, and that is

138.6*10^6 calculations, or say, 138.6 megacalculations.

The IBM does 138.6 megacalculations in 1 micro second, which is still astonishing, by the way

6 0

3 years ago

If the half-life of tritium (hydrogen-3) is 12.3 years, how much of

tatyana61 [14]

Answer:

0.0000076 grams

Explanation:

We're given the half life of Tritium to be 12.3 years. In order to find out the amount of substabce remaining:

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Now what is half life? It means the time taken for a given quantity of an element to lose half it's mass.

So in 12.3 years we can find that The amount of 250 g of Tritium will be 250/2 = 125 g. In 24.6 years we'll have 125/2 = 62.5 g

So now we can devise a formula:

$m = \frac{original \: amount}{ {2}^{n} }$

Where m is the remaining amount and n is th number of half lives in the time given.

Using this formula we can calculate:

$m = \frac{10}{ {2}^{20.325} }$

Doing this calculation we get:

$m = 0.0000076 \: g$

As we can see a very small value remains.

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3 years ago

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elixir [45]

Because it is if you know you know and it is also helping the sentwcnde and air and confiscation

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2 years ago