Why are radio waves considered harmless while ultraviolet waves and x-rats considered harmful

On another planet gravity has a value of 5.5 m/s . If an object is dropped how long will it take to fall 53 m?

Nikolay [14]

Answer:

4.4 seconds

Explanation:

Given:

a = -5.5 m/s²

v₀ = 0 m/s

y₀ = 53 m

y = 0 m

Find: t

y = y₀ + v₀ t + ½ at²

0 = 53 + 0 + ½ (-5.5) t²

0 = 53 − 2.75 t²

t = 4.39

Rounded to two significant figures, it takes 4.4 seconds for the object to land.

7 0

3 years ago

Are fat fish more likely to have broad stripes than thin fish?

maw [93]

yes, just like human skin. The bigger you grown the more your skin stretches, I a fish is bigger their skin will stretch leading to broad stripes.

7 0

3 years ago

A ship maneuvers to within 2.46×10³ m of an island’s 1.80 × 10³ m high mountain peak and fires a projectile at an enemy ship 6.1

Nesterboy [21]

Answer:

The distance close to the peak is 597.4 m.

Explanation:

Given that,

Distance of the first ship from the mountain $d=2.46\times10^{3}\ m$

Height of island $h=1.80\times10^{3}\ m$

Distance of the enemy ship from the mountain $d'=6.10\times10^{2}\ m$

Initial velocity $v=2.55\times10^{2}\ m/s$

Angle = 74.9°

We need to calculate the horizontal component of initial velocity

Using formula of horizontal component

$v_{x}=v\cos\theta$

Put the value into the formula

$v_{x}=2.55\times10^{2}\cos74.9$

$v_{x}=66.42\ m/s$

We need to calculate the vertical component of initial velocity

Using formula of vertical component

$v_{y}=v\sin\theta$

Put the value into the formula

$v_{y}=2.55\times10^{2}\sin74.9$

$v_{y}=246.19\ m/s$

We need to calculate the time

Using formula of time

$t=\dfrac{d}{v_{x}}$

$t=\dfrac{2.46\times10^{3}}{66.42}$

$t=37.03\ sec$

We need to calculate the height of the shell on reaching the mountain

Using equation of motion

$H= v_{y}t-\dfrac{1}{2}gt^2$

Put the value in the equation

$H=246.19\times37.03-\dfrac{1}{2}\times9.8\times(37.03)^2$

$H=2397.4\ m$

We need to calculate the distance close to the peak

Using formula of distance

$H'=H-h$

Put the value into the formula

$H'=2397.4-1800$

$H'=597.4\ m$

Hence, The distance close to the peak is 597.4 m.

6 0

3 years ago

I need c only please answer it

Elodia [21]

It will be moving at high speeds

5 0

3 years ago

Which of these items are made of cells? Check all that apply.

Katen [24]

Answer:

The correct answers are: Bacteria, Horses, Humans and Mushrooms.

Explanation:

All living organisms are made up of cells. A cell is a microscopic atomic unit and is made up of cytoplasm, one or more nuclei, and a membrane.

They are divided into eukaryotic cells (with nucleus) and prokaryotic cells (they do not have a nucleus).

Depending on the number of cells that living organisms have, they can be classified as single-celled organisms, which are made up of one cell. For example bacteria.

Or they can be multicellular organisms, formed by two or more cells, for example horses.

8 0

3 years ago

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