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3 years ago

A train travels 79 kilometers in 2 hours, and then 77 kilometers in 3 hours. What is its average speed?

1 answer:

4 0

Average speed=total distance traveled/time. Total distance=the sum of the two short distances=79*2+77*3=389 km. Total time used to travel is 2+3=5 hr. Average speed is 389/5=77.8 km/hr.

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Below are three graphs. The shape of graph 3 shows that the current flowing through this component is __________ proportional to

dalvyx [7]

The relationship between variables might be either directly porportional to each other or inversely proportional to each other. <em>For instance, the current flowing is _</em><em><u>directly</u></em><em>_ </em><em>proportional to the potential difference across</em> it.

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Since I do not have the graph, I will propose two potential options and I will describe each of them.

I suggest you to choose the one that matches the shape of graph 3.

<h3>Graphs</h3>

Probably your graph is composed of the X and Y axes, perpendicularly placed, in a way in which four quadrants are formed.

You might see that one of the axes represents the current (I), and the other one represents the potential difference (V).

And a straight line that represents the relationship between the current and the potential difference.

The direction of the straight line reflects the relationship between variables.

The change on each variable is proportional to the change on the other variable. Now we have to analyze how that change occurs.

<h3 /><h3>Option 1 </h3>

<em>The current flowing through this component is __</em><u><em>DIRECTLY</em></u><em>__ proportional to the potential difference across it</em>.

If this is the case of your graph, you should see the straight line crossing from the left inferior quadrant to the right superior one.

The direction of the line suggests that one of the variables increases as the other one increases too. <em>The current increases as the potential increases. </em>

<h3 /><h3 /><h3>Option 2 </h3>

<em>The current flowing through this component is __</em><u><em>INVERSELY</em></u><u><em>_</em></u><em>_ proportional to the potential difference across it.</em>

If this is the case of your graph, you should see the straight line crossing the right quadrant from the superior left corner to the inferior right one.

The direction of the line suggests that the variable represented in the Y ax decreases as the other one increases.

For instance, The current decreases as the potential increases. Or the potential decreases as the current increases.

In the attached files you will find graphs of both options.

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You can learn more about the Ohm's law at

brainly.com/question/17286882?referrer=searchResults

You can learn more about the relationship between variables at

brainly.com/question/16937826?referrer=searchResults

brainly.com/question/21627823?referrer=searchResults

6 0

2 years ago

A truck of mass 8000 kg is moving with a velocity of 50 km/h and collides with a bus of mass 5000 kg coming from opposite direct

liraira [26]

Answer:

A: 456

B: Because the shoes press down on the mud and get taken in

C:643

D:Because e = mc2 divided by 3 equals a = 3 equals 4.321a

Explanation:

6 0

2 years ago

Before the fission process takes place, lead-207 is bombarded with neutrons, it can change into

Oduvanchick [21]

Lead-207 can change into Lead-208.

When Lead-207 is bombarded with neutrons, the atom acquires the neutron. Adding a neutron only changes the mass number of the atom. This does not involve change in the identity of the atom. So, Lead-207 can change into Lead-208 without change in its chemical properties.

8 0

3 years ago

Read 2 more answers

Set the initial bead height to 3.00 m. Click Play. Notice that the ball makes an entire loop. What is the minimum height require

strojnjashka [21]

Answer:

h> 2R

Explanation:

For this exercise let's use the conservation of energy relations

starting point. Before releasing the ball

Em₀ = U = m g h

Final point. In the highest part of the loop

Em_f = K + U = ½ m v² + ½ I w² + m g (2R)

where R is the radius of the curl, we are considering the ball as a point body.

I = m R²

v = w R

we substitute

Em_f = ½ m v² + ½ m R² (v/R) ² + 2 m g R

em_f = m v² + 2 m g R

Energy is conserved

Emo = Em_f

mgh = m v² + 2m g R

h = v² / g + 2R

The lowest velocity that the ball can have at the top of the loop is v> 0

h> 2R

3 0

2 years ago

We can see Objects because of

Amiraneli [1.4K]

Answer:

I believe it's A.)

Explanation:

Although light comes into our atmosphere through refraction, it reaches our eyes only through reflection from objects. So when light rays reflect off an object and enter the eyes through the cornea you can then see that object.

Hope this helps you out : )

7 0

3 years ago