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3 years ago

13

Olympic gold medalist Michael Johnson runs one time around the track 400 meters in 38 seconds what is his displacement what is h

is average velocity

1 answer:

Sveta_85 [38]3 years ago

8 0

Displacement = 0, assuming that he runs back to original position
Average velocity is displacement/ time, since displacement =0, velocity is also 0

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What will happen to the force between 2 charged objects if the mass of one of the charges is doubled and the distance between th

bekas [8.4K]

The size of the force varies inversely as the square of the distance between the two charges. Therefore, if the distance between the two charges is doubled, the attraction or repulsion becomes weaker, decreasing to one-fourth of the original value

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2 years ago

A total of 25.6 kJ of heat energy is added to a 5.46 L sample of helium at 0.991 atm. The gas is allowed to expand against a fix

bagirrra123 [75]

Answer:

(a) W = 1329.5 J = 1.33 KJ

(b) ΔU = 24.27 KJ

Explanation:

(a)

Work done by the gas can be found by the following formula:

$W = P\Delta V$

where,

W = Work = ?

P = constant pressure = (0.991 atm)( $\frac{101325\ Pa}{1\ atm}$ ) = 100413 Pa

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Therefore,

W = (100413 Pa)(0.01324 m³)

<u>W = 1329.5 J = 1.33 KJ</u>

<u></u>

(b)

Using the first law of thermodynamics:

ΔU = ΔQ - W (negative W for the work done by the system)

where,

ΔU = change in internal energy of the gas = ?

ΔQ = heat added to the system = 25.6 KJ

Therefore,

ΔU = 25.6 KJ - 1.33 KJ

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3 0

3 years ago

Match the following items.

Ray Of Light [21]

Answer:

Je ne Sachez que Qu’est-ce que le

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2 years ago

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3 years ago

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3 years ago