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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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rjkz [21]

Answer:

1200KJ

Explanation:

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P (rotor-loss) = 3 x K.E

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After coming to zero, the motor again goes back to running speed of 1175 rpm but in opposite direction. The KE in this case would be;

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2 years ago

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Bezzdna [24]

Answer:

Explanation:

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Code:

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6 0

2 years ago

A fatigue test was conducted in which the mean stress was 90 MPa (13050 psi), and the stress amplitude was 190 MPa (27560 psi).

Gwar [14]

Answer:

a) 280MPa

b) -100MPa

c) -0.35

d) 380 MPa

Explanation:

GIVEN DATA:

mean stress $\sigma_m = 90MPa$

stress amplitude $\sigma_a = 190MPa$

a) $\sigma_m =\frac{\sigma_max+\sigma_min}{2}$

$90 =\frac{\sigma_{max}+\sigma_{min}}{2}$ --------------1

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$190 = \frac{\sigma_{max}-\sigma_{min}}{2}$ -----------2

solving 1 and 2 equation we get

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$=\frac{-100}{280} = -0.35$

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$=(\sigma_{max} -\sigma_{min})$

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3 years ago

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cupoosta [38]

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3 years ago

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Answer:

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5 0

2 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?