Ask question

Ask question

All categories

3 years ago

11

HELP PLEASE! I am taking a quiz and im completely lost

2 answers:

notka56 [123]3 years ago

5 0

Answer:

B?

Explanation:

Ann [662]3 years ago

4 0

Answer:

The answer is B. Matter and energy cannot enter or leave the system when the thermos lid is on tightly.

Hope this helps

You might be interested in

THE RIGHT ANSWER WILL RECEIVE A BRAINLESS AND POINTS AND THANKS!!!

poizon [28]

Answer:

391.67Hz

Explanation:

The fundamental frequency formula in string is expressed as;

Fo = V/2L

V is the velocity of the wave = 329m/s

L is the length of the string = 42cm = 0.42m

Substitute

Fo = 329/2(0.42)

Fo = 329/0.84

Fo = 391.67Hertz

Hence the fundamental frequency of a mandolin string is 391.67Hz

4 0

3 years ago

A ladder is balanced against a wall without moving. What<br> must be true about this ladder?

Mandarinka [93]

Answer:a no net force

Explanation: google lol

6 0

3 years ago

Consider a wave along the length of a stretched slinky toy, where the distance between coils increases and decreases. What type

GrogVix [38]

Answer:

"Longitudinal wave" is the appropriate answer.

Explanation:

Generating waves whenever the form of communication being displaced in a similar direction as well as in the reverse way of the wave's designated points, could be determined as Longitudinal waves.
A wave running the length of something like a Slinky stuffed animal, which expands as well as reduces the spacing across spindles, produces a fine image or graphic.

3 0

3 years ago

Read 2 more answers

You are standing in a building whose height (40m) you throw a ball downward at a angle of -30 at a speed of (10m/s) acceleration

jeyben [28]

Answer: 3.41 s

Explanation:

Assuming the question is to find the time $t$ the ball is in air, we can use the following equation:

$y=y_{o}+V_{o}sin \theta t-\frac{1}{2}gt^{2}$

Where:

$y=0m$ is the final height of the ball

$y_{o}=40 m$ is the initial height of the ball

$V_{o}=10 m/s$ is the initial velocity of the ball

$t$ is the time the ball is in air

$g=9.8 m/s^{2}$ is the acceleration due to gravity

$\theta=30\°$

Then:

$0 m=40 m+(10 m/s)(sin(30\°))t-\frac{1}{2}9.8 m/s^{2}t^{2}$

$0 m=40 m+5m/s t-4.9 m/s^{2}t^{2}$

Multiplying both sides of the equation by -1 and rearranging:

$4.9 m/s^{2}t^{2}-5m/s t-40 m=0$

At this point we have a quadratic equation of the form $at^{2}+bt+c=0$ , which can be solved with the following formula:

$t=\frac{-b \pm \sqrt{b^{2}-4ac}}{2a}$

Where:

$a=4.9$

$b=-5$

$c=-40$

Substituting the known values:

$t=\frac{-(-5) \pm \sqrt{(-5)^{2}-4(4.9)(-40)}}{2(4.9)}$

Solving the equation and choosing the positive result we have:

$t=3.41 s$ This is the time the ball is in air

5 0

4 years ago

A resistor of 5 Ω is placed in a circuit. The voltage drop across the resistor is 12 V. What is the current through the resistor

Kaylis [27]

<span>Data:

</span>R = 5 Ω
U = 12 V
i = ?
<span>
Formula:

</span> $U = R*i$ → $i = \frac{U}{R}$ <span>

Solving:

</span> $i = \frac{U}{R}$
$i = \frac{12}{5}$
$\boxed{i = 2.4A}$

Answer:

<span>The current through the resistor is 2.4 Amperes</span><span>

</span>

5 0

3 years ago