I need help with question 4

In a standard tensile test a steel rod of 22-mm diameter is subjected to a tension force of 75kN. Knowing that v = 0.30 and E =

VladimirAG [237]

Answer:

(a) Elongation of rod = 0.19732 mm

(b) Change in diameter = 0.00651 mm

Explanation:

Circular area at end of steel rod = pi * diameter^2 / 4

$Area = pi * (22 * 10^-^3)/4$

Area = 3.801 * 10^(-4) meter squared

Stress = force / area

Stress = 75000 / (3.801 * 10^-4)

Stress = 197316495 Pa OR 0.197 GPa

Modulus of elasticity = stress / strain

200 = 0.19732 / Strain

Strain = 0.0009866 (longitudinal)

(a) Strain = change in length / initial length

0.0009866 = Elongation of rod / 200

Elongation of rod = 0.19732 mm

(b) Poisson ratio = lateral strain / longitudinal strain

0.3 = lateral strain / 0.0009866

Lateral strain = 0.000296

Lateral strain = Change in diameter / original diameter

0.000296 = Change in diameter / 22

Change in diameter = 0.00651 mm

4 0

4 years ago

Read 2 more answers

Two children are pulling on opposite sides of a blanket. The brother is pulling with a force of 3 N. The sister is pulling with

Citrus2011 [14]

Let F1=Force exerted by the brother (+F1)
F1= Force exerted by the sister (-F2)

Fnet=(+F1) + (-F2)
Fnet= (+F1) + (-F2)
Fnet=F1 - F2
Fnet= (+3N)+(-5N)
Fnet= -2N

-F

towards the sister (-F) (greater force applied)

7 0

3 years ago

How long does it take decaying organisms to transform into fossil fuels?

taurus [48]

Answer:

Millions or hundreds of million of years

Explanation:

It takes a very long time for decaying substances to form fossil fuels. It takes around millions or hundreds of million of years for the transformation to occur. This explains why they aren’t renewable.

Decayed plant materials usually form coal while decayed animal materials form crude oil.

7 0

4 years ago

A helium balloon has an internal pressure of 2.5 atm when it occupies 4.5 L. If it was compressed until it had a pressure of 3.3

steposvetlana [31]

Answer: V = 3.4 L

Explanation: Use Boyle's Law to find the new volume. P1V1 = P2V2, derive for V2, then the formula will be V2= P1V1 / P2

V2 = 2.5 atm ( 4.5 L ) / 3.3 atm

= 3.4 L

4 0

4 years ago

Read 2 more answers

Show the weight of the ladder and draw the missing Frictional force.

madreJ [45]

Since there is no friction between the ladder and the wall, there can be no vertical force component. That's the tricky part ;)

So to find the weight, divide the 100N <em>normal</em> force by earths gravitational acceleration, 9.8m/s^2

$W = \frac{N}{g} = \frac{100N}{9.8m/s^{2}} = \frac{100}{9.8} = 10.2kg$

Then;
Draw an arrow at the base of the ladder pointing towards the wall with a value of 30N, to show the frictional force.

5 0

3 years ago