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Each liter of air has a mass of 1.80 grams. How many liters of air are contained in 2.5x10 to the third power kg of air?

valentinak56 [21]

Note: 2.5 * 10^3 kg = 2.5 * 10^3 * 10^3 = 2.5 * 10 ^6 g, Because 1 kg = 10^3 g

This is simple proportion

1.80 grams of air has a volume of 1 liter.

1 gram of air would have a volume of (1/1.8) liter

Therefore, 2.5 * 10^6 g would have: 2.5*10^6 * (1/1.8) = 1.3888 * 10^6 liters of air.

5 0

3 years ago

Why do you think soccer is an important sport?

Ostrovityanka [42]

Answer:

Soccer is a great way to maintain health, fitness, strength, and endurance. Soccer can help with cardiovascular health, lower body fat and improves muscle tone, increases muscle and bone strength, and improves health due to shifting between walking, running, and sprinting. Soccer can also promote teamwork and sharing, increase skills in concentration, persistence, and self-discipline, and can provide an opportunity to build your confidence and self-esteem, and it can also reduce anxiety.

Explanation:

4 0

3 years ago

A block of mass 0.490 kg is pushed against a horizontal spring of negligible mass until the spring is compressed a distance x. T

Dennis_Churaev [7]

Answer:

The value of x is $x = 0.1955\ m$

The value of the velocity at the top is $v_{top} = 2.25 \ m/s$

Explanation:

The diagram of this process is on the first uploaded image

From the question we are told that

The mass of the block is $m_b = 0.490kg$

The distance of compression is $x$

The force constant is $k = 450 N/m$

The radius of the circular track is $R =1.00m$

The speed at the bottom of the track is $v_A = 13.4 \ m/s$

The frictional force experienced is $F_f = 7.00 \ N$

Now looking at this process we see that the potential energy of the spring is been transformed into the kinetic energy of the block . So,

$PE \ of \ spring = KE \ of \ block$

mathematically i.e

$\frac{1}{2}k x^2 = \frac{1}{2} m_bv^2_A$

$0.5 * 450 * x^2 = 0.5 * 0.490 * 13.4^2$

Making x the subject of the formula

$x = \sqrt{\frac{0.5 * 0.490 * 13.4^2}{ 0.5 * 450} }$

$= 0.1955\ m$

The average workdone by friction is $W_f = F_f * \pi$

Here $\pi is \ the\ net\ displacement$

$W_f = 7 * 3.142$

$= 21.99 J$

The kinetic energy at the bottom is

$KE = \frac{1}{2} * 0.490 * 13.4^2$

$= 43.99 \ N$

The potential energy gained at the top of the circle is

$PE = m_bgh$

Here h is the height which is equal to d(diameter) = 2r = 2 × 1 = 2 m and

g is acceleration due to gravity $= 9.8m/s^2$

Now substituting values

$PE = 0.490 * 9.8 *2$

$=9.604 J$

Since energy is can not be created nor destroyed but transformed according to first law of thermodynamics

$KE_{at \bottom} = PE _ {\ at \ top } + W_f + KE_{\ at \ top}$

$43.99 = 9.604 +21.99 + [\frac{1}{2} m_b * v_{top} ^2]$

$12.369= [2.45* v_{top} ^2]$

$v_{top} =\sqrt{\frac{12.369}{2.45} }$

$= 2.25 \ m/s$

8 0

3 years ago

What happens when light enters a pair of glasses

alexdok [17]

Answer:

It refracts when it hits the glass.

6 0

3 years ago

Two basketball players are essentially equal in all respects. (They are the same height, they jump with the same initial velocit

ser-zykov [4K]

The reaction time of Boris is t(r), so before that, Boris will not have jumped. Thus, H(b)(t) = 0
The vertical displacement will simply be
D(t) = H(a)(t)

7 0

3 years ago