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3 years ago

What do you think of the category of polymer for making a helmet?

Engineering

2 answers:

Mice21 [21]3 years ago

8 0

Answer: Find the answer in the explanation

Explanation:

Helmets are manufactured by the use of different categories of polymer. The common material used for manufacturing of helmets are:

1. Polycarbonate

2. Styrofoam

3. Foam

4. Acrylic and polycarbonate

5. Nylon

All the polymer used for the manufacturing of helmets fall under synthetic and semi synthetic categories of polymer.

The styrofoam is classified under addition polymerization. While the nylon is classified under condensation polymerization.

The low density polythene used is classified as branch chains polymer. While the polycarbonate is of high tensile strength with strong mechanical properties.

jarptica [38.1K]3 years ago

3 0

I think that is a very good idea

;)

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3 years ago

A fire hose nozzle has a diameter of 1.125 in. According to some fire codes, the nozzle must be capable of delivering at least 2

Furkat [3]

Answer:

$P_{1} = 403,708\,kPa\,(58.553\,psi)$

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$P_{1} = P_{2}+ \frac{1}{2}\cdot \rho v^{2}$

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$v\approx 24.592\,\frac{m}{s}\,(80.682\,\frac{ft}{s} )$

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7 0

3 years ago

Read 2 more answers

Wattage is:

Ksju [112]

Answer:

c.Both A and B.

Explanation:

the wattage is c and d

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3 years ago

Problem 34.3 The elevation of the end of the steel beam supported by a concrete floor is adjusted by means of the steel wedges E

Natasha2012 [34]

The image is missing, so i have attached it.

Answer:

A) P = 65.11 KN

B) Q = 30 KN

Explanation:

We are given;

The end reaction of the beam; F = 100KN

Coefficient of static friction between two steel surfaces;μ_ss = 0.3

Coefficient of static friction between steel and concrete;μ_sc = 0.6

So, F1 = μ_ss•F =0.3 x 100 = 30 KN

F2 = μ_ss•N_EF = 0.3N_EF

From the screen shot, we see that the angle is 12°

Sum of forces in the Y-direction gives;

F2•sin12 - N_EF•cos12 + 100 = 0

Rearranging gives;

N_EF•cos12 - F2•sin12 = 100

Let's put 0.3N_EF for F2 to give;

N_EF•cos12 - 0.3N_EF•sin12 = 100

Thus;

N_EF(0.9158) - 0.1247 = 100

N_EF(0.9781) = 100 + 0.1247

N_EF = 100.1247/0.9158

N_EF = 109.33 KN

Thus, F2 = 0.3N_EF = 0.3 x 109.33 = 32.8 KN

Wedge will move if;

P = (F1 + F2cos12 + N_EFsin12)

Thus;

P = 10 + (32.8 x 0.9781) + (109.33 x 0.2079)

P ≥ 65.11 KN

B) For static equilibrium, Q = F1

Thus, Q = 30 KN

3 0

4 years ago

What do you think of the category of polymer for making a helmet?​

What do you think of the category of polymer for making a helmet?