Ask question

Ask question

All categories

3 years ago

15

12. Rainbows occur at __________. A. 40–42 degrees above the horizon B. at or below 25 degrees above the horizon C. the horizon

D. 60–75 degrees above the horizon.

1 answer:

murzikaleks [220]3 years ago

8 0

Answer:

the right answer is option C

Explanation:

at the horizon

You might be interested in

If cooling occurred at the bottom of a lake instead of its surface, the lake

AlladinOne [14]

No because the top has more oxygen to it which will break the particles up and have them freeze easier.

so if something froze at the bottom of the lake it would float to the top and that's why water always freezes from the top down :))

5 0

3 years ago

Read 2 more answers

A model rocket rises with constant acceleration to a height of 4.2 m, at which point its speed is 27.0 m/s. How much time does i

geniusboy [140]

Answers:

a) $t=0.311 s$

b) $a=86.847 m/s^{2}$

c) $y=1.736 m$

d) $V=17.369 m/s$

Explanation:

For this situation we will use the following equations:

$y=y_{o}+V_{o}t+\frac{1}{2}at^{2}$ (1)

$V=V_{o} + at$ (2)

Where:

$y$ is the <u>height of the model rocket at a given time</u>

$y_{o}=0$ is the i<u>nitial height </u>of the model rocket

$V_{o}=0$ is the<u> initial velocity</u> of the model rocket since it started from rest

$V$ is the <u>velocity of the rocket at a given height and time</u>

$t$ is the <u>time</u> it takes to the model rocket to reach a certain height

$a$ is the <u>constant acceleration</u> due gravity and the rocket's thrust

<h2>a) Time it takes for the rocket to reach the height=4.2 m</h2>

The average velocity of a body moving at a constant acceleration is:

$V=\frac{V_{1}+V_{2}}{2}$ (3)

For this rocket is:

$V=\frac{27 m/s}{2}=13.5 m/s$ (4)

Time is determined by:

$t=\frac{y}{V}$ (5)

$t=\frac{4.2 m}{13.5 m/s}$ (6)

Hence:

$t=0.311 s$ (7)

<h2>b) Magnitude of the rocket's acceleration</h2>

Using equation (1), with initial height and velocity equal to zero:

$y=\frac{1}{2}at^{2}$ (8)

We will use $y=4.2 m$ :

$4.2 m=\frac{1}{2}a(0.311)^{2}$ (9)

Finding $a$ :

$a=86.847 m/s^{2}$ (10)

<h2>c) Height of the rocket 0.20 s after launch</h2>

Using again $y=\frac{1}{2}at^{2}$ but for $t=0.2 s$ :

$y=\frac{1}{2}(86.847 m/s^{2})(0.2 s)^{2}$ (11)

$y=1.736 m$ (12)

<h2>d) Speed of the rocket 0.20 s after launch</h2>

We will use equation (2) remembering the rocket startted from rest:

$V= at$ (13)

$V= (86.847 m/s^{2})(0.2 s)$ (14)

Finally:

$V=17.369 m/s$ (15)

5 0

3 years ago

Which statement best describes how scientists and engineers work together in the research and development cycle? A. Scientists t

Pavlova-9 [17]

Answer:

c

Explanation:

7 0

4 years ago

Read 2 more answers

How many types air<br>I need a formula of calculating the s i unti of force

yKpoI14uk [10]

The si unit of force is newton.

so, F is eqal to m*g

4 0

3 years ago

Read 2 more answers

A girl and a boy pull in opposite directions on strings attached to each end of a spring balance. Each child exerts a force of 2

BabaBlast [244]

Answer:

yo they deleted my answer. The answer is 0N

Explanation:

so when two forces pull on an object from opposite sides with the same force (in this case its 20N), then the object is in equilibrium at 0N.

So its clear that there is one person on the the opposite side.

SOOO generally<u>: (left or down) would be considered </u><u>negative</u><u> in an equation. And the other person (right or up) would be considered </u><u>positive</u><u>.</u> So if both forces are the same numbers on opposite sides then the answer is 0 (if you add both of them).

<em>0 is the number of equilibrium.</em>

OK, so the equation would be -20N + 20N and then badda bing badda boom viola, the answer: 0N

thanks for coming to my TED talk. I hope they don't delete this answer.

5 0

3 years ago