Ask question

Ask question

All categories

Marina CMI [18]

3 years ago

7

In an experiment, students roll several hoops down the same incline plane. Each hoop has the same mass but a different radius. E

ach hoop rolls down the incline without slipping. Which of the following graphs best shows the linear speed V of the hoops at the bottom of the incline as a function of the radius r of the hoop?

1 answer:

insens350 [35]3 years ago

5 0

Answer:

The graph should have velocity (v) on the y-axis and radius (r) on the x-axis. It will have a straight, horizontal line that goes across the graph.

Explanation:

$KE=\frac{1}{2} I(omega)^{2}$

Shown above is the formula for Kinetic Energy in rotational terms. I'm new to brain.ly so I couldn't insert the omega symbol, sorry about that. Omega can be replaced with $\frac{v^{2} }{r^2}$ . Moment of Inertia (I) can be replaced with $mr^2$ .

The equation becomes $KE=\frac{1}{2} mr^2(\frac{v^2}{r^2} )$ .

The r's cancel out, making the different radii negligible, causing a straight horizontal line.

You might be interested in

A convex mirror of focal length 34 cm forms an image of a soda bottle at a distance of 18 cm behind the mirror. The height of th

Mademuasel [1]

<h2>Answers:</h2>

In convex mirrors the focus is virtual and the focal distance is negative. This is how the reflected rays diverge and only their extensions are cut at a point on the main axis, resulting in a virtual image of the real object .

<h2 /><h2>a) Position of the soda bottle (the object) </h2><h2 />

The Mirror equation is:

$\frac{1}{f}=\frac{1}{u}+\frac{1}{v}$ (1)

Where:

$f$ is the focal distance

$u$ is the distance between the object and the mirror

$v$ is the distance between the image and the mirror

We already know the values of $f$ and $v$ , let's find $u$ from (1):

$u=\frac{v.f}{v-f}$ (2)

Taking into account the explanation at the beginign of this asnswer:

$f=-34cm$ and $v=-18cm$

The <u>negative signs</u> indicate the <u>focal distance</u> and the <u>distance between the image and the mirror are virtual </u>

Then:

$u=\frac{(-18cm)(-34cm)}{-18cm-(-34cm)}$

$u=38.25cm$ (3) >>>>Position of the soda bottle

<h2>b) magnification of the image </h2><h2 />

The magnification $m$ of the image is given by:

$m=-\frac{v}{u}$ (4)

$m=-\frac{(-18cm)}{38.25cm}$

$m=0.47$ (5)>>>the image is 0.47 smaller than the object

<h2>The fact that this value is positive means the image is upright </h2>

<h2>c) Describe the image </h2><h2 />

According to the explanations and results obtained in the prior answers, the correct option is 9:

<h2>The image is <u>virtual, upright, smaller</u> than the object </h2><h2 /><h2>d) Height of the soda bottle (object) </h2>

Another way to find the magnification is by the following formula:

$m=\frac{h_{i}}{h_{o}}$ (6)

Where:

$h_{i}$ is the image height

$h_{o}$ is the object height

We already know the values of $m$ and $h_{i}$ , let's find $h_{o}$ :

$h_{o}=\frac{h_{i}}{m}$ (7)

$h_{o}=\frac{6.8cm}{0.47}$

$h_{o}=14.46cm$ (8) >>>height of thesoda bottle

6 0

3 years ago

The dry adiabatic rate of change for unsaturated air is 10°c/1000 m. what does this mean

brilliants [131]

Adiabatic rate is used to describe the change in temperature as a result of the rising or the sinking of an air parcel.

Knowing that the dry adiabatic rate of change for unsaturated air is 10°C/1000 m means that the temperature of the unsaturated air parcel would increase (get warmer) as the air parcel sinks and will decrease (get cooler) as the air parcel rises.

Hope this helps :)

3 0

4 years ago

A weed eater does 21 kJ of work in 0.750 h. What power does it develop?

myrzilka [38]

Answer:

$p = \frac{w}{t}$

21kj÷0.750

28w

6 0

3 years ago

A pen rolls off a 0.55–meter high table with an initial horizontal velocity of 1.2 meters/second. At what horizontal distance fr

levacccp [35]

To calculate the horizontal distance traveled by the ball, we first calculate the total time it takes to reach the ground as follows:

t = √[2y/g] = <span>√[2(0.55) / 9.81]
t = 0.33 s

The horizontal distance would be

</span><span>X = Vx*t = 1.2*√[2*.55/9.8] = 0.4 m
</span>
Hope this helps.

4 0

3 years ago

Read 2 more answers

He electron cloud is the predicted location for

DanielleElmas [232]

Answer:

A) Electrons only

Explanation:

In quantum mechanics, "electron cloud" refers to the region of space where electrons can be found in an atom. In fact, in quantum mechanics, it is not possible to predict the exact position of the electrons, so there is a region where electrons have a certain probability to be found.

7 0

3 years ago