1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Marrrta [24]
2 years ago
5

A helicopter, starting from rest, accelerates straight up from the roof of a hospital. The lifting force does work in raising th

e helicopter. An 790-kg helicopter rises from rest to a speed of 7.0 m/s in a time of 3.0 s. During this time it climbs to a height of 7.2 m. What is the average power generated by the lifting force?
Physics
1 answer:
LuckyWell [14K]2 years ago
6 0

Answer:

25032.47 W

Explanation:

Power is the time rate of doing work, hence,

P = Work done(non conservative) / time

Work done (non conservative) is given as:

W = total K. E. + total P. E.

Total K. E. = 0.5mv²- 0.5mu²

Where v (final velocity) = 7.0m/s, u (initial velocity) = 0m/s

Total P. E. = mgh(f) - mgh(i)

Where h(f) (final height) = 7.2m, h(i) (initial height) = 0 m

=> W = 0.5mv² - mgh(f)

P = [0.5mv² - mgh(f)] / t

P = [(0.5*790*7²) - (790*9.8*7.2)] / 3

P = (19355 + 55742.4) / 3 = 75097.4/3

P = 25032.47 W

You might be interested in
What is polygamy? Explain please:)
Mariulka [41]

I always thought that 'polygamy' refers to the social system in which a man
may have more than one wife, and I thought there's some other word for
where a woman is married to more than one man. 

But when I went to look it up just now to answer your question, (which by the
way you could also have done very easily), I found a definition that says it's a
"state of marriage between many spouses".  That doesn't specify genders, so
I guess it means any marriage that involves more than two people, no matter
how the genders may be represented or distributed within it.

5 0
3 years ago
Read 2 more answers
A mass is placed at the end of a spring. It has starting velocity of V & allowed to oscillate freely. If the mass has a star
LiRa [457]

Answer:

Equation for SHM can be written

V = w A cos w t        where w is the angular frequency and the velocity is a                                         maximum at t = 0

V1 = w1  A cos w1 t

V2 = w2 A cos w2 t

V2 / V1 = w2 / w1     since cos X t = 1 if t = zero

V2 / V1 = 2 pi f2 / (2 pi f1) = f2 / f1 = T1 / T2

If the velocity is twice as large the period will be 1/2 long

8 0
2 years ago
Calculate the intensity of current flowing through a computer that consumes 180W and operates at 120 V.
padilas [110]

Answer:

C) 1.5 A

Explanation:

P = IV

180 W = I (120 V)

I = 1.5 A

5 0
3 years ago
Layers in Earth's atmosphere are defined as regions in which _____.
Solnce55 [7]

Answer:

b. different types of weather occur

Explanation:

the temperture varies as one moves higher up, the higher one goes the cooler the temperature becomes. So that creates a change in weather condition.

6 0
3 years ago
The retina of the eye does all of the following except __________.
zvonat [6]

Answer:

C. rollback

Explanation:

The retina of the eye is located inside the eye making it impossible for the retina to roll back. Only the eye itself can rollback.

8 0
3 years ago
Other questions:
  • Un tren emplea cierto tiempo en recorrer 240 km. Si la velocidad hubiera sido 20 km por hora mas que la que llevaba hubiera tard
    13·1 answer
  • Help pls i give brainielest
    14·1 answer
  • A beaker has a mass of 125g. What is the mass of this beaker in decigrams
    10·1 answer
  • A 10-kg disk-shaped flywheel of radius 9.0 cm rotates with a rotational speed of 320 rad/s. part a determine the rotational mome
    10·1 answer
  • At the particle level, the weakest of the fundamental forces is:
    9·2 answers
  • un motor electric efectueaza un lucru mecanic de 864 j in 0.5 min.tensiunea la bornele sale este de 12v si este parcurs de un cu
    7·1 answer
  • Which statement best describes longitudinal waves
    10·1 answer
  • How much heat is needed to raise the temperature of 9g of water by 17oC?
    11·1 answer
  • Which force counteracts motion whenever two surfaces come into contact?.
    13·1 answer
  • 1. Is the image projected on a movie screen real or virtual? What about the image of yourself seen in a bathroom mirror?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!