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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

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SIZIF [17.4K]

Answer:

  • [\psi]= [Length^{-3/2}]
  • This means that the integral of the square modulus over the space is dimensionless.

Explanation:

We know that the square modulus of the wavefunction integrated over a volume gives us the probability of finding the particle in that volume. So the result of the integral

\int\limits^{x_f}_{x_0} \int\limits^{yf}_{y_0} \int\limits^{z_f}_{z_0} |\psi|^2 \, dz \,  dy \,  dx

must be dimensionless, as represents a probability.

As the differentials has units of length

[dx]=[dy]=[dz]=[Length]

for the integral to be dimensionless, the units of the square modulus of the wavefunction has to be:

[\psi]^2 = [Length^{-3}]

taking the square root this gives us :

[\psi] = [Length^{-3/2}]

5 0
3 years ago
How would you determine how much error there is between a vector addition and the real results
chubhunter [2.5K]
Desired operation: A + B = C; {A,B,C) are vector quantities. 

<span>Issue: {A,B} contain error (measurement or otherwise) </span>

<span>Objective: estimate the error in the vector sum. </span>

<span>Let A = u + du; where u is the nominal value of A and du is the error in A </span>
<span>Let B = v + dv; where v is the nominal value of B and dv is the error in B </span>
<span>Let C = w + dw; where w is the nominal value of C and dw is the error in C [the objective] </span>

<span>C = A + B </span>

<span>w + dw = (u + du) + (v + dv) </span>

<span>w + dw = (u + v) + (du + dv) </span>

<span>w = u+v; dw = du + dv </span>

<span>The error associated with w is the vector sum of the errors associated with the measured quantities (u,v)</span>
6 0
3 years ago
State the law of conservation of linear momentum using Newton's third law of deduce this ​
MArishka [77]

Answer:

Derivation of Conservation of Momentum

Applying Newton's third law, these two impulsive forces are equal and opposite i.e. is equal to the change in momentum of the first object. is equal to the change in momentum of the second object. This relation suggests that momentum is conserved during the collision.

Explanation:

Hope it helps!!!

7 0
2 years ago
A ball is thrown horizontally at a speed of 24 meters per second from the top of a cliff. if the ball hits the ground 4.0 second
Viktor [21]

Answer:

78.4 m

Explanation:

To obtain the height of the cliff;

We can use the Relation to obtain the final velocity, v

v = u + at

a = acceleration due to gravity = 9.8m/s²

v = 0 + (9.8*4)

v = 0 + 39.2

v = 39.2 m/s

To obtain the Height, S

v² = u² + 2aS

39.2^2 = 0 + 2(9.8)S

39.2^2 = 0 + 19.6S

1536.64 = 19.6S

S = 1536.64 / 19.6

S = 78.4 m

8 0
2 years ago
How fast does sound travel? A. 1,115 feet per second B. 1,000 feet per second C. 2,000 feet per second D. 2,115 feet per second.
lys-0071 [83]

Answer:

A

Explanation:

6 0
3 years ago
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