Ask question

Ask question

All categories

3 years ago

8

Paragraph summary on airplane history

1 answer:

irga5000 [103]3 years ago

4 0

Answer:The Wright brothers invented and flew the first airplane in 1903, recognized as "the first sustained and controlled heavier-than-air powered flight". ... Airplanes had a presence in all the major battles of World War II. The first jet aircraft was the German Heinkel He 178 in 1939.

Explanation:

You might be interested in

Which of the following is a valid reason why a scientist might reject a scientific theory

Flauer [41]

C I think hope it helps :)

6 0

3 years ago

Read 2 more answers

I need help with my autos

oksano4ka [1.4K]

Answer:

what is wrong with it and what is the question

Explanation:

6 0

3 years ago

A plane surface 25 cm wide has its temperature maintained at 80°C. Atmospheric air at 25°C ows parallel to the surface

Gre4nikov [31]

Answer:

See the detailed answer in attached file.

Explanation :

3 0

3 years ago

Two vertical, parallel clean glass plates are spaced a distance of 2mm apart. if the plates are placed in water, how high will t

Ulleksa [173]

Answer with Explanation:

The capillary rise in 2 parallel plates immersed in a liquid is given by the formula

$h=\frac{2\sigma cos(\alpha )}{\rho gd}$

where

$\sigma$ is the surface tension of the liquid

$\alpha$ is the contact angle of the liquid

$\rho$ is density of liquid

'g' is acceleratioj due to gravity

'd' is seperation between thje plates

Part a) When the liquid is water:

For water and glass we have

$\sigma =7.28\times 10^{-2}N/m$

$\alpha =0$

$\rho _{w}=1000kg/m^3$

Applying the values we get

$h=\frac{2\times 7.28\times 10^{-2}cos(0)}{1000\times 9.81\times 2\times 10^{-3}}=7.39mm$

Part b) When the liquid is mercury:

For mercury and glass we have

$\sigma =485.5\times 10^{-3}N/m$

$\alpha =138^o$

$\rho _{w}=13.6\times 10^{3}kg/m^3$

Applying the values we get

$h=\frac{2\times 485.5\times 10^{-3}cos(138)}{13.6\times 1000\times 9.81\times 2\times 10^{-3}}=-2.704mm$

The negative sign indicates that there is depression in mercury in the tube.

4 0

3 years ago

The flat-bed trailer carries two 2000-kg beams with the upper beam secured by a cable. The coefficients of static friction betwe

Lina20 [59]

Answer:

attached below

Explanation:

8 0

3 years ago