Ask question

Ask question

All categories

Anuta_ua [19.1K]

3 years ago

10

why can planes fly but boats cant and why can boats float but not planes and saying planes fly because of the wind or air is not

correct .

2 answers:

Aleksandr-060686 [28]3 years ago

4 0

Answer:

Planes can fly because they have wings and jet turbines and boats cant they need wings and planes cant float because there is to much weight

Tanya [424]3 years ago

4 0

Planes can fly because of their wings but they are too much weight to float :)

You might be interested in

How do scientists and engineers use math to help them?

VikaD [51]

Math (e.g., algebra, geometry, calculus, computer computation) is used both as a tool to create mathematical models that describe physical phenomena and as a tool to evaluate the merit of different possible solutions. ... In engineering, math and science are tools used within the engineering design process.
Biologists use math as they plot graphs to help them understand equations, run small “trial and error” tests with some sample numbers when developing algorithms, and use the R project for analyzing protein sequences and structures. Electrical engineers use math in many ways in their career. They use math to help design and test electrical equipment. They use math to calculate amp and volt requirements for electrical projects. They use math in creating computer simulations and designs for new products.

7 0

3 years ago

What is a network? I'LL MARK BRAINLEST

Jobisdone [24]

Answer:

hsjeeieoj eu sou ku nahi u have UCC guide to buying it and I he was a temporary password for bees and u h ki tarah nahi to ye sab se jyada nahi hota nahi to kabhi bhi hai ki wo to sirf Tum nahi hota

7 0

2 years ago

Read 2 more answers

Match the test to the property it measures.

Vinvika [58]

Answer:

a. Rockwell 3. hardness

b. Instron 2. stress vs strain

c. Charpy 1. impact strength

d. Fatigue 4. Endurance Limit

e. Brinell 3. hardness

f. Izod 1. impact strength

Explanation:

Izod and Charpy are the impact strength testing procedure of a material in which a heavy hammer is attached to an arm is released to impact on the test specimen. In Izod test the specimen with v-notch is held vertical with the notch facing outward while in Charpy test the specimen is supported horizontally with notch facing inward to the impacting hammer.

Instron testing system does universal testing of the material which gradually applies the load recording all the stresses and the corresponding strains until the material fails.

Fatigue is the property of a material due to which it fails under the repeated cyclic loading by the initiation and propagation of cracks. The property of a material resist failure subjected to infinite number of repeated cyclic loads below a certain stress limit.

Rockwell and Brinell are the hardness testing methods. In Rockwell test an intender ball is firstly pressed against the specimen using minor load for a certain time and then a major load is pressed against it for a certain time. After the intender is removed the depth of impression on the surface is measured while in case of Brinell hardness we apply only one load against the intender ball for a certain time and after its removal the radius of impression is measured.

7 0

3 years ago

The dam cross section is an equilateral triangle, with a side length, L, of 50 m. Its width into the paper, b, is 100 m. The dam

lisabon 2012 [21]

Answer:

Explanation:

In an equilateral trinagle the center of mass is at 1/3 of the height and horizontally centered.

We can consider that the weigth applies a torque of T = W*b/2 on the right corner, being W the weight and b the base of the triangle.

The weigth depends on the size and specific gravity.

W = 1/2 * b * h * L * SG

Then

Teq = 1/2 * b * h * L * SG * b / 2

Teq = 1/4 * b^2 * h * L * SG

The water would apply a torque of elements of pressure integrated over the area and multiplied by the height at which they are apllied:

$T1 = \int\limits^h_0 {p(y) * sin(30) * L * (h-y)} \, dy$

The term sin(30) is because of the slope of the wall

The pressure of water is:

p(y) = SGw * (h - y)

Then:

$T1 = \int\limits^h_0 {SGw * (h-y) * sin(30) * L * (h-y)} \, dy$

$T1 = \int\limits^h_0 {SGw * sin(30) * L * (h-y)^2} \, dy$

$T1 = SGw * sin(30) * L * \int\limits^h_0 {(h-y)^2} \, dy$

$T1 = SGw * sin(30) * L * \int\limits^h_0 {(h-y)^2} \, dy$

$T1 = SGw * sin(30) * L * \int\limits^h_0 {h^2 - 2*h*y + y^2} \, dy$

T1 = SGw * sin(30) * L * (h^2*y - h*y^2 + 1/3*y^3)(evaluated between 0 and h)

T1 = SGw * sin(30) * L * (h^2*h - h*h^2 + 1/3*h^3)

T1 = SGw * sin(30) * L * (h^3 - h^3 + 1/3*h^3)

T1 = 1/3 * SGw * sin(30) * L * h^3

To remain stable the equilibrant torque (Teq) must be of larger magnitude than the water pressure torque (T1)

1/4 * b^2 * h * L * SG > 1/3 * SGw * sin(30) * L * h^3

In an equilateral triangle h = b * cos(30)

1/4 * b^3 * cos(30) * L * SG > 1/3 * SGw * sin(30) * L * b^3 * (cos(30))^3

SG > SGw * 4/3* sin(30) * (cos(30))^2

SG > 1/2 * SGw

For the dam to hold, it should have a specific gravity of at leas half the specific gravity of water.

This is avergae specific gravity, including holes.

6 0

2 years ago

what can be done to prevent bridges from collapsing? ( give at least two examples)

ryzh [129]

Explanation:

the owner of the bridge and some workers

4 0

2 years ago