Consider the classic problem with holiday lights, one little bulb goes out and the whole string goes out. First consider a strin
1 answer:
Answer:
<em>a. 0.33 Amp</em>
<em>b. 2.4 Volt</em>
<em>c. 0</em>
<em>d. 2.45 Amp</em>
<em>e. Infinite</em>
<em>f. Series is safer</em>
Explanation:
<u>Series Connection of Resistors</u>
When two or more resistors are connected in series, the current through each one of them is the same, and the voltage divides depending on the particular value of each resistance. If all the resistances are equal, then the voltage is equally divided.
a. The string of 50 bulbs is connected to a 120 VAC outlet and consumes 40 W. The power of a circuit is given by
Solving for I
Since all the bulbs are connected in series the current is the same for all of them.
b. The voltage is equally divided, so each bulb has 120/50= 2.4 V
c. If one of the bulbs burns out and its resistance becomes infinite, then the series circuit is open and no current flows through it, neither through the rest of the bulbs. The typical case of the whole string going out.
d. If one of the bulbs short circuits, the resistance of that bulb is zero and the voltage is distributed by the 49 remaining bulbs. Thus the new current is
e. If the bulbs were connected in parallel, all of them would have the same voltage, and the total current will be equally divided among them. In that case, a short circuit in one of the bulbs will cause a parallel short, theoretically producing an infinite current and making the short circuit protection blow up.
f. The condition described above makes the strings be made of series-connected bulbs which is safer than the parallel circuit. If a single bulb shorts, the entire string goes out in a series connection, but the breaker would trigger disconnection of the house circuit if it's a parallel connection. That is why we must deal with unusable strings instead of burning cables.
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Answer:
What is the speed of the mountain lion as it leaves the ground?
9.98m/s
At what angle does it leave the ground?
50.16°
Explanation:
This is going to be long, so if you want to see how it was solved refer to the attached solution. If you want to know the step by step process, read on.
To solve this, you will need use two kinematic equations and SOHCAHTOA:
With these formulas, we can derive formulas for everything you need:
Things you need to remember:
- A projectile at an angle has a x-component (horizontal movement) and y-component (vertical movement), which is the reason why it creates an angle.
- Treat them separately.
- At maximum height, the vertical final velocity is always 0 m/s going up. And initial vertical velocity is 0 m/s going down.
- Horizontal movement is not influenced by gravity.
- acceleration due to gravity (a) on Earth is constant at 9.8m/s
First we need to take your given:
10.0 m long (horizontal) and maximum height of 3.0m (vertical).
What your problem is looking for is the initial velocity and the angle it left the ground.
Vi = ? Θ =?
Vi here is the diagonal movement and do solve this, we need both the horizontal velocity and the vertical velocity.
Let's deal with the vertical components first:
We can use the second kinematic equation given to solve for the vertical initial velocity but we are missing time. So we use the first kinematic equation to derive a formula for time.
Since it is at maximum height at this point, we can assume that the lion is already making its way down so the initial vertical velocity would be 0 m/s. So we can reduce the formula:
From here we can derive the formula of time:
Now we just plug in what we know:
Now that we know the time it takes to get from the highest point to the ground. The time going up is equal to the time going down, so we can use this time to solve for the intial scenario of going up.
Remember that going up the vertical final velocity is 0m/s, and remember that gravity is always moving downwards so it is negative.
So we have our first initial vertical velocity:
Viy = 7.66m/s
Next we solve for the horizontal velocity. We use the same kinematic formula but replace it with x components. Remember that gravity has no influence horizontally so a = 0:
But horizontally, it considers the time of flight, from the time it was released and the time it hits the ground. Also, like mentioned earlier the time going up is the same as going down, so if we combine them the total time in flight will be twice the time.
T= 2t
T = 2 (0.782s)
<em>T = 1.564s</em>
<em>So we use this in our formula:</em>
<em></em>
Vix=6.39m/s
Now we have the horizontal and the vertical component, we can solve for the diagonal initial velocity, or the velocity the mountain lion leapt and the angle, by creating a right triangles, using vectors (see attached)
To get the diagonal, you just use the Pythagorean theorem:
c²=a²+b²
Using it in the context of our problem:
The lion leapt at 9.98m/s
Using SOHCAHTOA, we know that we can TOA to solve for the angle, because we have the opposite and adjacent side:
The lion leapt at an angle of 50.16°.
