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2 years ago

How many molecules are there in 39 grams of water

Physics

1 answer:

Llana [10]2 years ago

8 0

Answer:

39 g H2O contains 1.3 ×1024molecules H2O.

Explanation:

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Explain whether demand is likely to be elastic or inelastic for Big Macs. A. Elastic comma since many other fast food items coul

anyanavicka [17]

Answer:

A - elastic since many other fast food items could be considered close substitutes.

Explanation:

The price elasticity of demand is how much the demand of the Big Macs will change due to a 1% change in price. Should the elasticity be greater than 1, the Big Macs will be elastic. Should it be less than 1, the Big Macs are inelastic.

Demand elasticity is calculated as the percentage change in quantity demanded divided by a percentage change in price.

Since Big Macs are (i) a luxury good, and (ii) have close substitutes (other burgers available at McDonalds and other fast food stores), we will say their elasticity is greater than 1.

This means that the demand of Big Macs will change due to a 1% increase in price due to the presence of close substitutes.

3 0

2 years ago

A ball is thrown vertically upward, which is the positive direction. A little later, it returns to its point of release. The bal

Aleks [24]

Answer:

The initial velocity of the ball is 39.2 m/s in the upward direction.

Explanation:

Given:

Upward direction is positive. So, downward direction is negative.

Tota time the ball remains in air (t) = 8.0 s

Net displacement of the ball (S) = Final position - Initial position = 0 m

Acceleration of the ball is due to gravity. So, $a=g=-9.8\ m/s^2$ (Acting down)

Now, let the initial velocity be 'u' m/s.

From Newton's equation of motion, we have:

$S=ut+\frac{1}{2}at^2$

Plug in the given values and solve for 'u'. This gives,

$0=8u-0.5\times 9.8\times 8^2\\\\8u=4.9\times 64\\\\u=\frac{4.9\times 64}{8}\\\\u=4.9\times 8=39.2\ m/s$

Therefore, the initial velocity of the ball is 39.2 m/s in the upward direction.

3 0

3 years ago

What percentage of the takeoff velocity did the plane gain when it reached the midpoint of the runway? a plane accelerates from

ElenaW [278]

When is at the end of the runway the velocity of the plane is given by the equation $vf^{2}=0+2*a*s$ where s=1800 m is the runway length. Thus
$vf^{2}=2*5*1800=18000 (m/s)^{2}$
$vf =134.164 (m/s)$

At half runway the velocity of the plane is
$v^{2}=2*5* \frac{1800}{2}=9000 ( \frac{m}{s} )^{2}
$
$v= \sqrt{9000}=94.87 ( \frac{m}{s})$

Therefore at midpoint of runway the percentage of takeoff velocity is
‰ $P= \frac{v}{vf}= \frac{94.87}{134.164}=0.707$

6 0

2 years ago

According to research, college graduates are more likely to engage in all of the following EXCEPT:

Ksivusya [100]

Strange question. I’d say B)

7 0

2 years ago

Read 2 more answers

Jane and John Doppler effect

UkoKoshka [18]

Answer:

To summarize, Jane's star has a red light and is traveling towards the Earth while John's star has a blue light and is traveling away from the Earth. This is a prime example of the Doppler Effect in motion. The stars look different because they are traveling in different directions.

4 0

2 years ago