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
7nadin3 [17]
3 years ago
9

A kite is an airfoil that uses the wind to produce a lift. Held in place by a string, a kite can remain aloft indefinitely. The

diamond kite is a particularly simple kite. As the wind passes under the lower surface of the diamond kite, it bends away from the surface and slows down. The air pressure under the lower surface is

Engineering
1 answer:
Anna71 [15]3 years ago
4 0

Answer:

<em>a) results in an increased pressure.</em>

<em>b) results in a pressure lower than the atmospheric pressure.</em>

<em>c) The direction of the overall force is upwards.</em>

<em>d) other forces are the weight, drag, and tension on the string.</em>

<em>e) the extra weight due to the tail adds drag and keeps the nose of the kite pointing upwards and the kite generally stable.</em>

<em></em>

Explanation:

a) As the wind passes under the lower surface of the diamond kite, it slows down. The slowing down of the wind under the lower surface results in an increased air pressure under the lower surface which now exceeds the pressure at the upper surface of the diamond kite, generating more lift upwards.

b) As the wind passes over the upper surface of the diamond kite, turbulence occurs resulting in pressure lower than the atmospheric pressure. This results in a reduce air drag on the kite.

c) The direction of the overall force exerted by the air on the kite is upwards.

d) Other force that acts on the kite in the air are; gravity force (due to the weight of the kite), drag (due to air flow around the kite), and tension force on the string from you. Once at the maximum height, the approximate net force on the kite is zero (provided the kite is stable at this height).

e) The extra weight of the kite due to the tail adds drag at the bottom of the kite, keeping the nose pointing upwards, and keeps the kite stable.

You might be interested in
A 2-cm-diameter vertical water jet is injected upward by a nozzle at a speed of 15 m/s. Determine the maximum weight of a flat p
Ede4ka [16]

Answer:58.28 N

Explanation:

Given data

dia. of nozzle \left ( d\right )=2 cm

initial velocity\left ( u\right )=15 m/s

height\left ( h\right )=2m

Now velocity of jet at height of 2m

v^2-u^2=2gh

v^2=15^2-2\left ( 9.81\right )\left ( 2\right )

v=\sqrt{185.76}=13.62 m/s

Now\ forces\ on\ plate\ are\ weight\left ( Downward\right ) and jet\ force\left ( upward\right )

equating them

W=\left ( \rho Av\right )v

W=10^{3}\times \frac{\pi}{4}\left ( 0.02\right )^2\times 13.62^2

W=58.28 N

7 0
4 years ago
The difference between an initial condition and a boundary condition for conduction in a solid is:___________
leva [86]

Answer:

c. an initial condition specifies the temperature at the start of the problem and a boundary condition provides information about temperatures on the boundaries.

Explanation:

Conduction refers to the transfer of thermal energy or electric charge as a result of the movement of particles. When the conduction relates to electric charge, it is known as electrical conduction while when it relates to thermal energy, it is known as heat conduction.

In the process of heat conduction, thermal energy is usually transferred from fast moving particles to slow moving particles during the collision of these particles. Also, thermal energy is typically transferred between objects that has different degrees of temperature and materials (particles) that are directly in contact with each other but differ in their ability to accept or give up electrons.

Any material or object that allow the conduction (transfer) of electric charge or thermal energy is generally referred to as a conductor. Conductors include metal, steel, aluminum, copper, frying pan, pot, spoon etc.

Hence, the difference between an initial condition and a boundary condition for conduction in a solid is that an initial condition specifies the temperature at the start of the problem and a boundary condition provides information about temperatures on the boundaries.

7 0
3 years ago
With 64 KB of memory and 8 bits in each memory location, how wide should the address bus be to access all 64 KB of memory? (k =
marishachu [46]

Answer:

16-bit wide

Explanation:

In order to find the width of the address bus, we need first to know how many memory cells it is needed to address.

If the size memory is 64 KB, this means that the memory size, in bytes, is equal to the following quantity:

64 KB = 2⁶ * 2¹⁰ bytes = 2¹⁶ bytes.

In order to address this quantity of cell positions, the address bus must be able to address 2¹⁶ bytes, so it must have 16-bit wide.

3 0
3 years ago
It is appropriate to use the following yield or failure criterion for ductile materials (a) Maximum shear stress or Tresca crite
Nataly [62]

Answer:

(b)Distortion energy theory.

Explanation:

The best suitable theory for ductile material:

       (1)Maximum shear stress theory (Guest and Tresca theory)

It theory state that applied maximum shear stress should be less or equal to its maximum shear strength.

      (2)Maximum distortion energy theory(Von Mises henkey's        theory)

It states that maximum shear train energy per unit volume at any point  is equal to strain energy per unit volume under the state of uni axial stress condition.

But from these two Best theories ,suitable theory is distortion energy theory ,because it gives best suitable result for ductile material.

6 0
3 years ago
Air at 26 kPa, 230 K, and 220 rn/s enters a turbojet engine in flight. The air mass flow rate is 25 kg/s. The compressor pressur
Paha777 [63]

Answer:

Explanation:

Answer:

Explanation:

Answer:  

Explanation:  

This is a little lengthy and tricky, but nevertheless i would give a step by step analysis to make this as simple as possible.  

(a). here we are asked to determine the Temperature and Pressure.  

Given that the properties of Air;  

ha = 230.02 KJ/Kg  

Ta = 230 K  

Pra = 0.5477  

From the energy balance equation for a diffuser;  

ha + Va²/2 = h₁ + V₁²/2  

h₁ = ha + Va²/2 (where V₁²/2 = 0)  

h₁ = 230.02 + 220²/2 ˣ 1/10³  

h₁ = 254.22 KJ/Kg  

⇒ now we obtain the properties of air at h₁ = 254.22 KJ/Kg  

from this we have;  

Pr₁ = 0.7329 + (0.8405 - 0.7329)[(254.22 - 250.05) / (260.09 - 250.05)]  

Pr₁ = 0.77759  

therefore T₁ = 254.15K  

P₁ = (Pr₁/Pra)Pa  

= 0.77759/0.5477 ˣ 26  

P₁ = 36.91 kPa  

now we calculate Pr₂  

Pr₂ = Pr₁ (P₂/P₁) = 0.77759 ˣ 11 = 8.55349  

⇒ now we obtain properties of air at  

Pr₂ = 8.55349 and h₂ = 505.387 KJ/Kg  

calculating the enthalpy of air at state 2  

ηc = h₁ - h₂ / h₁ - h₂  

0.85 = 254.22 - 505.387 / 254.22 - h₂  

h₂ = 549.71 KJ/Kg  

to obtain the properties of air at h₂ = 549.71 KJ/Kg  

T₂ = 545.15 K

⇒ to calculate the pressure of air at state 2

P₂/P₁ = 11

P₂ = 11 ˣ 36.913  

p₂ = 406.043 kPa

but pressure of air at state 3 is the same,

i.e. P₂ = P₃ = 406.043 kPa

P₃ = 406.043 kPa

To obtain the properties of air at  

T₃ = 1400 K, h₃ = 1515.42 kJ/Kg and Pr = 450.5

for cases of turbojet engine,

we have that work output from turbine = work input to the compressor

Wt = Wr

(h₃ - h₄) = (h₂ - h₁)

h₄ = h₃ - h₂ + h₁  

= 1515.42 - 549.71 + 254.22

h₄ = 1219.93 kJ/Kg

properties of air at h₄ = 1219.93 kJ/Kg

T₄ = 1140 + (1160 - 1140) [(1219.93 - 1207.57) / (1230.92 - 1207.57)]

T₄ = 1150.58 K

Pr₄ = 193.1 + (207.2 - 193.1) [(1219.93 - 1207.57) / (1230.92 - 1207.57)]

Pr₄ = 200.5636

Calculating the ideal enthalpy of the air at state 4;

Лr = h₃ - h₄ / h₃ - h₄*

0.9 = 1515.42 - 1219.93 / 1515.42 - h₄  

h₄* = 1187.09 kJ/Kg

now to obtain the properties of air at h₄⁻ = 1187.09 kJ/Kg

P₄* = 179.7 + (193.1 - 179.7) [(1187.09 -1184.28) / (1207.57 - 1184.28)]

P₄* = 181.316

P₄ = (Pr₄/Pr₃)P₃       i.e. 3-4 isentropic process

P₄ = 181.316/450.5 * 406.043

P₄ = 163.42 kPa

For the 4-5 process;

Pr₅ = (P₅/P₄)Pr₄

Pr₅ = 26/163.42 * 200.56 = 31.9095

to obtain the properties of air at Pr₅ = 31.9095

h₅= 724.04 + (734.82 - 724.04) [(31.9095 - 3038) / (32.02 - 30.38)]

h₅ = 734.09 KJ/Kg

T₅ = 710 + (720 - 710) [(31.9095 - 3038) / (32.02 - 30.38)]

T₅ = 719.32 K

(b) Now we are asked to calculate the rate of heat addition to the air passing through the combustor;

QH = m(h₃-h₂)

QH = 25(1515.42 - 549.71)

QH = 24142.75 kW

(c). To calculate the velocity at the nozzle exit;

we apply steady energy equation of a flow to nozzle

h₄ + V₄²/2 = h₅ + V₅²/2

h₄  + 0  = h₅₅ + V₅²/2

1219.9 ˣ 10³ = 734.09 ˣ 10³ + V₅²/2

therefore, V₅ = 985.74 m/s

cheers i hope this helps

6 0
4 years ago
Other questions:
  • Tadpoles raised in water with atrazine levels of 0.1 ppb should produce a higher percentage of male frogs with gonadal abnormali
    13·1 answer
  • A circuit with ____ -diameter connecting wires at a _____ temperature will have the least electrical resistance.
    13·1 answer
  • Suppose an underground storage tank has been leaking for many years, contaminating a groundwater and causing a contaminant conce
    8·1 answer
  • why HF (hydrogen fluoride) has higher boiling temperature than HCl (hydrogen chloride), even thought HF has lower molecular weig
    8·1 answer
  • How are scientific discoveries used in engineering design?
    12·1 answer
  • The controlled variable in a closed-loop system is the direction of a robot arm. Initially, it is at 50o; then it is commanded t
    12·1 answer
  • Parting tool purpose
    13·1 answer
  • What parts do all circuits have in common?
    9·2 answers
  • A 1.9-mm-diameter tube is inserted into an unknown liquid whose density is 960 kg/m3, and it is observed that the liquid rises 5
    7·1 answer
  • Why does my man bun not have its own erodynamics
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!