The student hung the plastic strip over the wooden rod. The ends of the strip moved away from each other

The "Garbage Project" at the University of Arizona reports that the amount of paper discarded by households per week is normally

Lorico [155]

Answer:

54%

Explanation:

We are given that

S.D=4.2 lb

Mean= $\mu=9.4 lb$

We have to find the percentage of household throw out at least 9 lb of paper a week.

Normal distribution formula :

$P(X\geq a)=P(z\geq \frac{a-\mu}{\sigma})$

We have a=9

$P(X\geq 9)=P(z\geq \frac{9-9.4}{4.2})=P(z\geq -0.1)$

$P(X\geq 9)=1-P(z$

$P(X\geq 9)=1-0.4602=0.5398\times 100=54$ %

Hence, the percentage of household throw out at least of paper a week=54%

7 0

3 years ago

Particles in a medium through which a sound wave is traveling

GuDViN [60]

Answer:

EL SONIDO PUEDE VIAJAR POR CUALQUIER MEDIO MATERIAL, COMO

AIRE, NITRÓGENO, AGUA, TITANIO, ETC... ASÍ QUE EL

SONIDO VIAJA A TRAVÉS DE MOLÉCULAS.

Explanation:

7 0

3 years ago

A spherical wave with a wavelength of 2.0 mm is emitted from the origin. At one instant of time, the phase at rrr = 4.0 mm is πr

max2010maxim [7]

Complete Question

A spherical wave with a wavelength of 2.0 mm is emitted from the origin. At one instant of time, the phase at r_1 = 4.0 mm is π rad. At that instant, what is the phase at r_2 = 3.5 mm ? Express your answer to two significant figures and include the appropriate units.

Answer:

The phase at the second point is $\phi _2 = 1.57 \ rad$

Explanation:

From the question we are told that

The wavelength of the spherical wave is $\lambda = 2.0 \ mm = \frac{2}{1000} = 0.002 \ m$

The first radius is $r_1 = 4.0 \ mm = \frac{4}{1000} = 0.004 \ m$

The phase at that instant is $\phi _1 = \pi \ rad$

The second radius is $r_2 = 3.5 \ mm = \frac{3.5}{1000} = 0.0035 \ m$

Generally the phase difference is mathematically represented as

$\Delta \phi = \phi _2 - \phi _1$

this can also be expressed as

$\Delta \phi = \frac{2 \pi }{\lambda } (r_2 - r_1 )$

So we have that

$\phi _2 - \phi _1 = \frac{2 \pi }{\lambda } (r_2 - r_1 )$

substituting values

$\phi _2 - \pi = \frac{2 \pi }{0.002 } ( 0.0035 - 0.004 )$

$\phi _2 = \frac{2 \pi }{0.002 } ( 0.0035 - 0.004 ) + 3.142$

$\phi _2 = 1.57 \ rad$

7 0

3 years ago

A rod attracts a positively charged hanging ball. the rod is?a) negativeb) positivec) neutrald) either negative or neutrale) eit

makvit [3.9K]

Answer:

The correct option is a

Explanation:

This question seeks to test a general rule in physics (on charges) which states that <u>like charges repel but unlike charges attract</u>. This means that, a negatively charged substance will repel or not attract another negatively charged material and the same applies to a positively charged substance also. However, a <u>negatively charged substance will attract a positively charged material and vice versa,</u> hence only a negatively charged rod will attract a positively charged hanging ball.

8 0

4 years ago

Lead-202 has a half-life of 53,000 years. How long will it take for 15/16 of a sample of lead-202 to decay?

ohaa [14]

Answer:

C. 212,000 years

Explanation:

believe me it's correct.....and you're welcome :)

4 0

3 years ago