Which sentence describes Newton's first law?

7 One lb of Refrigerant 134a contained within a piston–cylinder assembly undergoes a process from a state where the temperature

julsineya [31]

Answer:

$\Delta S = S_2-S_1 = 0.08835 \frac {BTU} {Lb ^ {\circ} R}$

Explanation:

A) In order to solve the table it is necessary to consult tables A11-E and A10E for refrigerant R134-a

In this way we obtain that:

$S_1 = S_f = 0.0648 \frac {BTU} {Lb. ^ {\circ} R}$

In this way,

$S_2 = S_f + x_2 (S_g-S_f) = 0.0902 + 0.5 (0.2161-0.0902)$

$S_2 = 0.15315 \frac {BTU} {Lb ^ {\circ} R}$

In this way the entropy change is,

$\Delta S = S_2-S_1 = 0.08835 \frac {BTU} {Lb. ^ {\°} R}$

B) Whenever entropy yields a positive result, the process can be carried out adiabatically.

7 0

3 years ago

An ammeter is connected in series with a resistor of unknown resistance R and a DC power supply of known emf e. A student uses t

rosijanka [135]

Answer:

B:The actual power dissipated by the resistor is less than P because the ammeter had some resistance.

Explanation:

Here,power has been calculated using current I and total EMF \ε . So,P=EMF*current= ε I will represent total power dissipated in resistor and ammeter.

Now, this total power P has been dissipated in both resistor and ammeter. So, power dissipated in resistor must be less than P as some power is also dissipated in ammeter because it has non-zero resistance.

So, the answer is B:The actual power dissipated by the resistor is less than P because the ammeter had some resistance.

Note that option A,C and E are ruled out as they state power dissipated by resistor is greater than or equal to P which is false.

Also,option D is ruled out as ammeter is connected in series.

8 0

4 years ago

In the United States, where can volcanoes be found?

Sedbober [7]

<span>The volcanoes of USA are located along the west coast, at the subduction of the Pacific and North American tectonic plates. During the 20th century there were only two eruptions in continental USA; Lassen in 1915, and Mt St Helens in 1980. Alaska and Hawaii contain currently active volcanoes. hope this helps:)</span>

7 0

3 years ago

Need help with the questons asap

mina [271]

Which questions? i need to see the actual question, did you like upload them to your profile now?

4 0

4 years ago

At 13:20 on the last Friday in September, 1989 a frantic call was received at the local police station. There had been a serious

astraxan [27]

The kinematics and conservation of momentum relationships allow to find the results for the questions about the measurements and conditions to know the accident conditions are:

1) The principles of conservation of momentum and kinematics.

2) $\theta = tan^{-1} \frac{P_{01}}{p_{02}}$

3) The factors that influence the direction and distance traveled are:

The initial speed of the vehicles

The mass of the vehicles

Pavement conditions: dry, wet, humid, with dirt or loose sand.

1) Kinematics studies the movement of bodies, they look for relationships between position, speed and acceleration.

To analyze the accident, you must answer a question such as what speed the vehicles had before the accident, this is the initial speed of each one and their directions.

When reviewing the kinematics relationships we have.

$v^2 = v_o^2 - 2 a x$

Where the acceleration is given by Newton's second law.

fr = m a

The friction force is given by the expression.

fr = μ N

fr = μ mg

Let's Substitute.

μ m g = m a

a = μ g

The friction coefficient is tabulated, for different types of rubber, pavement and wet, dry conditions, etc.

Therefore, the researcher must measure the braking distance of the vehicles, which can be taken from the mark of the tires on the road and note the condition of the pavement if it is dry or wet and the visibility of the day.

This is the speed of the vehicles just after the impact, using the law of conservation of momentum you can find the speed of the vehicles before the impact

$p_o = p_f$ \f

Where this is a vector expression, which in general is solved with the components of each directional.

Consequently to answer the questions you must use the principles of conservation of momentum and kinematics.

2) If the vehicles travel at right angles and their masses are similar, the direction after the collision in each direction.

$tan \theta = \frac{p_{01}}{p_{02}}$

$\theta = tan ^{-1} \frac{p_{01}}{p_{02}}$

3) The factors that influence the direction and distance traveled are:

The initial speed of the vehicles

The mass of the vehicles

Pavement conditions: dry, wet, humid, with dirt or loose sand.

In conclusion, using the kinematics and conservation of momentum relationships, we can find the answers to the question about measurements and conditions to know the accident conditions are:

1) The principles of conservation of momentum and kinematics.

2) $\theta = tan^{-1} \frac{P_{01}}{p_{02}}$

3) The factors that influence the direction and distance traveled are:

The initial speed of the vehicles

The mass of the vehicles

Pavement conditions: dry, wet, humid, with dirt or loose sand.

Learn more about kinematics and momentum here: brainly.com/question/17304001

5 0

3 years ago