Ask question

Ask question

All categories

4 years ago

14

What controls the brain of a cell

1 answer:

olya-2409 [2.1K]4 years ago

6 0

The nucleus of course...<span />

You might be interested in

A ball is thrown upward from the top of a building at an angle of 30.0° to the horizontal and with

Ray Of Light [21]

Answer:

See below

Explanation:

Vertical position = 45 + 20 sin (30) t - 4.9 t^2

when it hits ground this = 0

0 = -4.9t^2 + 20 sin (30 ) t + 45

0 = -4.9t^2 + 10 t +45 = 0 solve for t =4.22 sec

max height is at t= - b/2a = 10/9.8 =1.02

use this value of 't' in the equation to calculate max height = 50.1 m

it has 4.22 - 1.02 to free fall = 3.2 seconds free fall

v = at = 9.81 * 3.2 = 31.39 m/s VERTICAL

it will <u>also</u> still have horizontal velocity = 20 cos 30 = 17.32 m/s

total velocity will be sqrt ( 31.39^2 + 17.32^2) = 35.85 m/s

Horizontal range = 20 cos 30 * t = 20 * cos 30 * 4.22 = 73.1 m

8 0

2 years ago

The U.S. Navy has long proposed the construction of extremely low frequency (ELF waves) communications systems; such waves could

Artyom0805 [142]

Answer:

length of a quarter wavelength antenna for transmitter elf waves are zero

Explanation:

Find the length of a quarter wavelength antenna for transmitter elf waves

Given information

frequency (ELF waves) → 77Hz

Speed of light → 3 $\times$ $10^8$ m/s

$v=\lambda f-------------1$

where

$\lambda\\$ → wavelength of the antenna

f → frequency of the ELF waves

$v$ → speed of light

so rewrite the equation in $\lambda$ from

$\lambda=\dfrac{v}{f}$

Substitute $3\times10^8m/s$ = $v$

Substitute 75Hz = f

$\lambda=\dfrac{3\times10^8m/s}{77Hz}$

$=3.9\times 10^6$ m

since we get this value,but this size of antenna mount on submarine is not possible.

so $\lambda$ is zero

6 0

3 years ago

A composite load consists of three loads connected in parallel. One draws 100 W at a PF of 0.92 lagging, another takes 250 W at

fenix001 [56]

Answer:

a) $I_{RMS} = 4.79 A$

b) $PF = 0.908$

Explanation:

Get the reactive powers for each of the loads:

Reactive power = Real Power * tanθ

For load 1

Active power, P₁ = 100 W

Power factor, $cos \theta_{1} = 0.92$

$\theta_{1} = cos^{-1} 0.92\\\theta_{1} = 23.074$

$Q_{1}= P_{1} tan \theta_{1} \\Q_{1}= 100tan 23.074\\Q_{1}= 42.60 W$

For load 2

Active power, P₂ = 250 W

Power factor, $cos \theta_{2} = 0.8$

$\theta_{2} = cos^{-1} 0.8\\\theta_{2} = 36.87$

$Q_{2}= P_{1} tan \theta_{2} \\Q_{2}= 250tan 36.87\\Q_{2}= 187.5 W$

For load 3

Active power, P₃ = 250 W

Power factor, $cos \theta_{3} = 1$

$\theta_{3} = cos^{-1} 1\\\theta_{3} =0$

$Q_{2}= P_{1} tan \theta_{3} \\Q_{3}= 150tan 0\\Q_{3}= 0 W$

Calculate the total reactive power, $Q_{net} = 42.6 + 187.5 + 0$

$Q_{net} = 230.1 W$

Calculate the total active power, $P_{net} = 100 + 250 + 150 = 500 W$

$S_{net} = P_{net} + Q_{net} \\S_{net} = 500 + j230.1$

$P_{net} = IVcos \theta_{net}$

$\theta_{net} = tan^{-1} \frac{230.1}{500} \\\theta_{net} = 24.712$

V = 115 $V_{rms}$

$500 = I_{RMS} * 115 cos 24.712\\I_{RMS} = 500/104.47\\ I_{RMS} = 4.79 A$

b) Power factor of the composite load is $cos\theta_{net}$

$\theta_{net} = 24.712\\PF = cos 24.712\\PF = 0.908$

4 0

3 years ago

If a pitcher throws a baseball 10 m in 30 seconds - what would be the average speed of the baseball

dangina [55]

S = d/t
S = 10m/30s
S = 0.33m/s

6 0

3 years ago

Silver is composed of a single type of atom and cannot be broken down into different substances. Silver is an example of a(n) __

ella [17]

Element. The answer is A.

6 0

4 years ago