How to find gravitational potential energy?

How long will it take for a sound impulse to travel through a copper rod 25 kilometers long?

jekas [21]

By conducting exhaustive, high-intensity online research for about 15 seconds, I found a source that says the speed of sound in copper is 4600 m/s. (You could easily have completed the same research project in about 1/3 of the time it took you to type and post the question here.)

Time it takes = (distance) / (speed)

Time = (25,000 meters) / (4600 m/s)

Time = (25 / 4.6) km-sec/km

Time = 5.43 seconds

4 0

3 years ago

What rhymes with leave

gayaneshka [121]

Peeve like a pet peeve

6 0

3 years ago

Read 2 more answers

6. The image to the right shows a moment of inertia

Trava [24]

The moment of inertia is the rotational analog of mass, and it is given by

the product of mass and the square of the distance from the axis.

The moment of inertia changes as the position of the weight is changed, which indicates that; statement is incorrect

Reasons:

The weight on each arm that have adjustable positions can be considered as point masses.

The moment of inertia of a point mass is I = m·r²

Where;

m = The mass of the weight

r = The distance (position) from the center to which the weight is adjusted

Therefore;

The moment of inertia, I ∝ r²

Which gives;

Doubling the distance from the center of rotation, increases the moment of inertia by factor of 4.

Therefore, the statement contradicts the relationship between the radius of rotation and moment of inertia.

Learn more about moment of inertia here:

brainly.com/question/4454769

7 0

2 years ago

Find the difference between two masses measured as 123.6 grams and 115.972 grams. Express the answer to the correct number of si

xxTIMURxx [149]

Answer:

The difference is 7.6 grams.

Explanation:

In mathematics the difference of two numbers is express as the subtraction between them:

$a-b$

So to find out the difference between the two measured masses, a will be represented by 123.6 grams since is the bigger number, and b by 115.972 grams.

Therefore, it is get:

$123.6grams-115.972grams = 7.6grams$

Hence, the difference is 7.6 grams.

The result of 7.628 will be expressed as 7.6 to have the correct number of significant figures.

Notice how that can be express in units of kilograms too since there is 1000 gram in 1 kilogram:

$7.6grams . \frac{1Kg}{1000grams}$ ⇒ $7.6x10^{-3}Kg$

8 0

3 years ago

Initially, a 2.00-kg mass is whirling at the end of a string (in a circular path of radius 0.750 m) on a horizontal frictionless

drek231 [11]

Answer:

$v_f = 15 \frac{m}{s}$

Explanation:

We can solve this problem using conservation of angular momentum.

The angular momentum $\vec{L}$ is

$\vec{L} = \vec{r} \times \vec{p}$

where $\vec{r}$ is the position and $\vec{p}$ the linear momentum.

We also know that the torque is

$\vec{\tau} = \frac{d\vec{L}}{dt} = \frac{d}{dt} ( \vec{r} \times \vec{p} )$

$\vec{\tau} = \frac{d}{dt} \vec{r} \times \vec{p} + \vec{r} \times \frac{d}{dt} \vec{p}$

$\vec{\tau} = \vec{v} \times \vec{p} + \vec{r} \times \vec{F}$

but, as the linear momentum is $\vec{p} = m \vec{v}$ this means that is parallel to the velocity, and the first term must equal zero

$\vec{v} \times \vec{p}=0$

so

$\vec{\tau} = \vec{r} \times \vec{F}$

But, as the only horizontal force is the tension of the string, the force must be parallel to the vector position measured from the vertical rod, so

$\vec{\tau}_{rod} = 0$