4. What is the value?<br> 5.function or not?

If a circle has a diameter of two what would the area be

Feliz [49]

Answer:

3.14

Step-by-step explanation:

d=2

A= pi*r^2 = pi*(d/2)^2 = pi*(2/2)^2= pi*1 =pi =3.14

4 0

3 years ago

Put the differential equation 9ty+ety′=yt2+81 into the form y′+p(t)y=g(t) and find p(t) and g(t). p(t)= help (formulas) g(t)= he

alexgriva [62]

Answer:

$p(t) = \frac{9t^{3} + 729t - 1}{e^{t}(t^{2} + 81) }$

g(t) = 0

And

The differential equation $9ty + e^{t}y' = \frac{y}{t^{2} + 81 }$ is linear and homogeneous

Step-by-step explanation:

Given that,

The differential equation is -

$9ty + e^{t}y' = \frac{y}{t^{2} + 81 }$

$e^{t}y' + (9t - \frac{1}{t^{2} + 81 } )y = 0\\e^{t}y' + (\frac{9t(t^{2} + 81 ) - 1}{t^{2} + 81 } )y = 0\\e^{t}y' + (\frac{9t^{3} + 729t - 1}{t^{2} + 81 } )y = 0\\y' + [\frac{9t^{3} + 729t - 1}{e^{t}(t^{2} + 81) } ]y = 0$

By comparing with y′+p(t)y=g(t), we get

$p(t) = \frac{9t^{3} + 729t - 1}{e^{t}(t^{2} + 81) }$

g(t) = 0

And

The differential equation $9ty + e^{t}y' = \frac{y}{t^{2} + 81 }$ is linear and homogeneous.

6 0

3 years ago

A man weighing 800 N is hanging from a 2 mm diameter titanium wire with a cross-section of 3 x 10^-6 m^2. Will the wire break?

DENIUS [597]

Answer:

Since stress is greater than ultimate strength, the wire will break.

Step-by-step explanation:

The titanium wire is experimenting an axial load. Ultimate strength equals $2.20\times 10^{8}\,Pa$ . The wire shall break if and only if stress is at least equal to ultimate strength. The equation for axial stress ( $\sigma$ ), measured in pascals, in the wire with circular cross-section is:

$\sigma = \frac{4\cdot F}{\pi\cdot D^{2}}$ (1)

Where:

$F$ - Axial force, measured in newtons.

$D$ - Cross-section diameter, measured in meters.

Please notice that axial force is the weight of the man hanging from wire.

If we know that $F = 800\,N$ and $D = 0.002\,m$ , then the axial stress experimented by the titanium wire is:

$\sigma = \frac{4\cdot (800\,N)}{\pi\cdot (0.002\,m)^{2}}$

$\sigma \approx 2.546\times 10^{8}\,Pa$

Since stress is greater than ultimate strength, the wire will break.

3 0

3 years ago

How do you write 1.5 × 104 in standard form?

rewona [7]

I'm assuming you meant 1.5 × 10⁴. Remember, when we write in standard form, you need to use ^ to denote it's 'to the power of'. So it would be 1.5 × 10^4.

I'm also assuming you meant in decimal form, because that's already in standard form.

However, the answer is 15,000. This is because you lose one zero when multiplying a decimal with one number after it. For each number after the decimal, you take off a zero. Therefore, the end number is 15,000.

5 0

3 years ago

Brady needs to cut a piece of scrapbook paper

dexar [7]

It is 10.2 centimeters so option A :)

6 0

3 years ago

Read 2 more answers

4. What is the value? 5.function or not?