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2 years ago

for the whole page done i reward u with 50 points i am very tired and i have many work to do so thank you guys for the help

Physics

2 answers:

REY [17]2 years ago

7 0

We will use Newton's second law

F=ma
m=F/a

m=5/5=1kg

#Box 2

m=5/0.75
m=6.67kg

#Box 3

5/4.3
m=1.16kg

First box has smallest mass

mezya [45]2 years ago

4 0

Answer:

Box 1

Explanation:

Formula we are using :

Force = mass × acceleration

mass = Force / acceleration (since mass needs to be found)

=============================================================

Box 1 :

⇒ mass = 5 N / 5 m/s²

⇒ mass = 1 kg

=========================================================

Box 2 :

⇒ mass = 5 N / 0.75 m/s²

⇒ mass = 5 × 4/3 = 20/3 kg

⇒ mass = 6.67 kg

===========================================================

Box 3 :

⇒ mass = 5 N / 4.3 m/s²

⇒ mass = 50/43 kg

⇒ mass = 1.16 kg

===========================================================

On comparing Box 1, Box 2, and Box 3, we understand that Box 1 has the smallest mass

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3 years ago

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Answer:

a) -0.0934 kJ/kg. K

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NOW,

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$P_2$ = pressure at location 2

We obtain the specific properties of air at temperature at $T_1$ = (67°C + 273)K = 340 K from the table A-22 ( Ideal gas properties of air)

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Equating our result to equation (1)

$s_2-s_1 \geq 0\\-0.0934 \leq 0$

Therefore , our assumption is wrong and the direction of flow is said to be from right to left.

We therefore conclude that the direction of flow is from right to left.

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