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2 years ago

Which of these steps would most likely be part of a lab procedure?

Physics

1 answer:

Snezhnost [94]2 years ago

8 0

Answer:

These are a part of lab procedures:

1. Write a hypothesis to answer a question.

2. Write a title at the top of a completed lab report.

3. Record the time to complete a chemical reaction.

These are NOT a part of lab procedures:

1. Create a question on the cause of a chemical reaction.

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A system consists of three particles with these masses and velocities: mass 3.00 kg, moving north at 3.00 m/s; mass 4.00 kg, mov

lions [1.4K]

Answer:

the total momentum is 8 .2 kg m/s in north direction.

Explanation:

given,

mass(m₁) 3.00 kg, moving north at v₁ = 3.00 m/s

mass(m₂) 4.00 kg, moving south at v₂ = 3.70 m/s

mass(m₃) 7.00 kg, moving north at v₃ = 2.00 m/s

north as the positive axis

south as the negative axis

now

total momentum = m₁v₁ + m₂ v₂ + m₃ v₃

total momentum = 3 x 3 - 4 x 3.7 + 7 x 2

= 9 - 14.8 + 14

= 8 .2 kg m/s

hence, the total momentum is 8 .2 kg m/s in north direction.

7 0

3 years ago

What math term is used to describe the shape of projectile motion?

algol13

Over short to medium distance, the shape of a projectile"s path is a PARABOLA.

8 0

3 years ago

A train moves at constant velocity of 50km/h. how far will it move in 0.5h?

Kobotan [32]

The formula for getting the distance will be distance = speed x time
                                                                               D = S x T
   speed or velocity = 50km/h
   time = 0.5 h
the equation will be done directly because it's already in it's SI units
            distance = 50km/h x 0.5h
            hour cancels hour and the equation remains = 50km x 0.5
                               Ans = 25 km
the train will move 25 km far in 0.5h

7 0

3 years ago

Air enters a turbine operating at steady state with a pressure of 75 Ibf/in.^2, a temperature of 800º R and velocity of 400 ft/s

Arturiano [62]

Answer:

(a) W/m = 49.334 Btu/lb

(b) $\frac{E_{d} }{m}$ = 22.12 Btu/lb

Explanation:

For the given problem, it can be assumed that the system is operating at steady state and the effects of potential energy can be neglected.

(a) Using the thermodynamic table for air.

At the temperature ( $T_{1}$ )of 800 ºR and pressure ( $P_{1}$ ) of 75 Ibf/in.^2, we can deduce that:

Specific enthalpy ( $h_{1}$ ) = 191.81 BTu/lb

Specific entropy ( $s_{1}$ ) = 0.6956 Btu/(lb.ºR)

At the temperature ( $T_{2}$ )of 600 ºR and pressure ( $P_{2}$ ) of 15 Ibf/in.^2, we can deduce that:

Specific enthalpy ( $h_{2}$ ) = 143.47 BTu/lb

Specific entropy ( $s_{2}$ ) = 0.6261 Btu/(lb.ºR)

The work done can be calculated using energy rate equation:

$\frac{W}{m} = \frac{Q}{m} + (h_{1} - h_{2}) + \frac{V_{1}^{2} - V_{2}^{2}}{2}$

Q/m = heat transfer = -2 Btu/lb

$V_{1}$ = 400 ft/s

$V_{2}$ = 100 ft/s

$\frac{W}{m} = -2 + (191.81 - 143.47) + \frac{400^{2} - 100^{2}}{2}*[tex]\frac{1}{2*32.2*778}$ [/tex] = -2 + 48.34 + 29.938 = 49.334 Btu/lb

(b) To calculate the exergy destruction, we will use the equation for exergy rate:

$\frac{E_{d} }{m} = [1-\frac{T_{o} }{T_{b} }](\frac{Q}{m}) - \frac{W}{m} + [(h_{1} - h_{2}) -T_{o}(s_{1} - s_{2}) + \frac{V^{2} _{1} - V_{2} ^{2}}{2}]$

The equation above is further simplified to:

$\frac{Ed}{m} = T_{o}[(s_{2} -s_{1}) - Rln\frac{P_{2} }{P_{1} } - \frac{Q/m}{T_{b} }]$

Using a reference temperature (To) = 500 °R

Average surface temperature (Tb = 620°R

$\frac{Ed}{m} = 500*[(0.6261 -0.6956) - (1.986/28.97)ln\frac{15 }{75 } - \frac{-2}{620}}]$

$\frac{E_{d} }{m}$ = 500*[-0.0695 +0.068688*1.609 +0.003225] = 22.12 Btu/lb

5 0

3 years ago

6. Протон с кинетична енергия Ek = 1,6.10 J, който се

anzhelika [568]

Answer:

Tahukah kamu, mengapa motor berhenti di depan lampu merah?

karena motornya direm. Coba kalau nggak direm bisa bahaya tuh.

Tebak binatang apa yang jago renang?

Bebek. Kalau ikan bukan renang tapi menyelam

Kenapa di rel kereta api ditaruh batu?

Soalnya kalau ditaruh duit nanti pada diambil.

3 0

2 years ago