Question 1 Multiple Choice Worth 2 points)

A Carnot engine whose high-temperature reservoir is at 620 k takes in 550 J of heat at this temperature in each cycle and gives

yarga [219]

Answer:

(a) W=217 J

(b) Tc=378K

(c) e=0.39=39%

Explanation:

For part (a)

We to calculate the mechanical work W the engine does. By knowing QC and QH can obtain the work using equation

W = IQHI — IQcl .....................eq(1)

Put given values for QH and QC into equation (1) to get

the mechanical work of the engine

W = 550 - 335

W=217 J

For part (b)

We want to determine the temperature of low temperature reservoir which means Tc

IQc|/|Qh| =TC/TH

for Tc

Tc=(IQc|/|Qh|)*TH

Now we can put values

Tc= 620K (335/ 550.1)

Tc=378K

For part (c)

Here we want to find the thermal efficiency (e) of the cycle

e=1-TC/TH

e=1-(378/620)

e=0.39=39%

6 0

3 years ago

A 30.4-newton force is used to slide a 40.0-newton crate a distance of 6.00 meters at constant speed along an incline to a verti

Angelina_Jolie [31]

Hi there!

Since the crate is being slid at a constant speed, the forces sum to 0 N. In this instance, the following forces occur in the axis of interest:

Wsinθ = downward acceleration along incline due to gravity (N)

Fκ = kinetic friction force along incline (N)

A = applied force (N)

The acceleration due to gravity and friction force act in the same direction, so:

Wsinθ + Fκ = A

Solve for sinθ using right triangle trigonometry:

sinθ = O/H = 3/6 = 0.5

Rearrange the equation for the force of kinetic friction and solve:

Fκ = A - 0.5W

Fκ = 30.4 - 20 = 10.4 N

Now, recall that:

Work = Force × displacement (W = F × d)

Since the box's displacement is in the same axis as the force but OPPOSITE direction, we must use:

W = Fdcosθ

Angle between displacement and friction force is 180°.

cos(180) = -1

Work done by friction = -Fd = -10.4(6) = -62.4 J

8 0

3 years ago

A wave has a wavelength of 11 mm and a frequency of 11 hertz. What is its speed?

eimsori [14]

Wave speed = frequency (in Hz) x wavelength (in m) so wave speed = 11 x 0.011 = 0.121 m/s

5 0

3 years ago

Read 2 more answers

PLEASE HELP

kogti [31]

Answer:

C. nuclear to electrical

6 0

3 years ago

Read 2 more answers

Are u god tell me u have to tell me are u a god

Allushta [10]

They tell me I'm a god, I'm lost in the facade

Six-feet off the ground at all times, I think I'm feelin' odd

No matter what I make, they never see mistakes

Makin' so much bread, I don't care that they're just being fake

They tell me they're below me, I act like I'm above

The people blend together but I would be lost without their love

Can you heal me? Have I gained too much?

When you become untouchable, you're unable to touch

Is there a real me? Pop the champagne

It hurts me just to think and I don't do pain

Stayin' still, eyes closed

Let the world just pass me by

Pain pills, nice clothes

If I fall, I think I'll fly

Touch me, Midas

Make me part of your design

None to guide us

I feel fear for the very last time.

7 0

3 years ago