The long handle on a rake is a ____

Consider 2 steel rods, A and B, B has three times the area and twice the length of A, so young modulus of B will be what factor

AVprozaik [17]

Answer:

$\frac{Y}{Y_o}$ = 2/3

Explanation:

The yuong modulus of a rod is defined as the relationship between the tensile strength and the strain

Y = $\frac{ \frac{F}{A} }{\frac{\Delta L}{L_o} }$

let's use the subscript "o" for rod A

I = $\frac{ \frac{F}{A_o} }{ \frac{\Delta L}{L_o} }$

tells us that rod B has

A = 3 A₀

L = 2 L₀

we substitute

Y = $\frac{ \frac{F}{A} }{ \frac{\Delta L}{L} }$

Y = $\frac{ \frac{F}{3A_o} }{ \frac{\Delta L}{ 2L_o} }$

y = ⅔ $\frac{ \frac{F}{A_o}}{ \frac{\Delta }{L_o} }$

substituting the value of Y₀

Y = ⅔ Y₀

$\frac{Y}{Y_o}$ = 2/3

5 0

3 years ago

A neighbor's child wants to go to a neighborhood carnival to experience the wild rides. The neighbor is worried about safety as

seraphim [82]

Answer:

No, the ride is not safe

Explanation:

From the diagram attached, it is seen that

$\sum f_{y} = 0$

$\tau cos \theta - W = 0$ ................(1)

$\sum f_{x} = 0$

$-ma + \tau sin \theta = 0$ .......(2)

$a = w^{2} r$

From the diagram, $r = Lsin \theta$

$a = w^{2} L sin \theta$

$w = \frac{2\pi }{T}$

$a = \frac{4\pi ^{2}L sin \theta }{T^{2} }$ ............(3)

Put (3) into (2)

$\tau sin \theta = \frac{4\pi ^{2}m L sin \theta }{T^{2} }$

$\tau = \frac{4\pi ^{2}m L }{T^{2} }$

w = weight of chair + weight of child = 50 + 10 = 60 lb

g = 32 ft/s²

m = w/g = 60/32 = 1.875

L = 30 ft

T = 3 secs

$\tau = \frac{4\pi ^{2}*1.875*30 }{0.3^{2} }$

$\tau = 246.74 lbs$

since 246.74 lbs > 200 lbs, it is not safe because the stationary chair will creak

6 0

3 years ago

Read 2 more answers

An automobile moves at a constant speed over the crest of a hill traveling at a speed of 88.5 km/h. At the top of the hill, a pa

Sergio039 [100]

Answer:

$r=61.65m$

Explanation:

Since the package remains in contact with the car's seat, the package's speed is equal to the car's speed. At the top on the mountain the package's centripetal force must be equal to its weight:

$mg=F_c$

The centripetal force is defined as:

$F_c=ma_c=\frac{mv^2}{r}$

Here v is the linear speed of the object and r is the radius of curvature. We need to convert the linear speed to $\frac{m}{s}$ :

$88.5\frac{km}{h}*\frac{1000m}{1km}*\frac{1h}{3600s}=24.58\frac{m}{s}$

Now, we calculate r:

$mg=\frac{mv^2}{r}\\r=\frac{v^2}{g}\\r=\frac{(24.58\frac{m}{s})^2}{9.8\frac{m}{s^2}}\\\\r=61.65m$

3 0

2 years ago

Which are properties of both a gas and a plasma? Check all that apply.

wlad13 [49]

<span>The answer is 4, 6 and 7. Gas and plasma share most similar properties. The difference lies in the fact that plasma is composed of ions and electrons (ionized gas) as opposed to gas that is composed of neutral molecules. Therefore plasma can conduct electricity while gas cannot. </span>

7 0

3 years ago

Read 2 more answers

If you push a 200 kg box with a horizontal force of 1,172 N and kinetic friction resists the motion with a force of 962 N, what

Lynna [10]

Answer:

a = 1.05m.s²

Explanation:

Fnet = m×a

Fapplied - friction = m×a

1172 - 962 = 200 × a

210 = 200a

a = 1.05

5 0

1 year ago

The long handle on a rake is a _____.