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3 years ago

When was the first electric typewriter produced and by what company

1 answer:

6 0

In 1920, after returning from Army service, he produced a successful model and in 1923 turned it over to the Northeast Electric Company of Rochester for development.

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How many joules is 3 lightning bolts?

pogonyaev

Answer:

one billion to ten billion joules.

Explanation:

To keep a 100-watt light bulb going for one second, one hundred joules of energy will be used.

6 0

2 years ago

Read 2 more answers

An organ pipe open at both ends has two successive harmonics with frequencies of 220 Hz and 240 Hz. What is the length of the pi

Harman [31]

Answer:

The length is $l = 8.6 \ m$

Explanation:

From the question we are told that

The frequencies of the two successive harmonics are $f_1 = 220 \ Hz$ , $f_2 = 240 \ Hz$

The speed of sound in the air is $v_s = 343 \ m/s$

Generally the frequency of a given harmonic is mathematically represented as

$f_n = \frac{n v }{2l}$

Here n defines the position of the harmonics

Now since the position of both harmonic is not know but we know that they successive then we can represented them mathematically as

$220 = \frac{n v}{2l}$

and

$240 = \frac{(n+1) v}{2l}$

$\frac{(n + 1 ) v}{2l} - \frac{n v}{2l} = 240-220$

=> $\frac{v}{2l} = 20$

=> $l = 8.6 \ m$

7 0

3 years ago

How and where is old oceanic crust destroyed?

sladkih [1.3K]

Answer:

It is destroyed in subduction zones. A Geologic process in which a tectonic plate made of dense lithospheric material melts or falls below a plate made of less-dense lithosphere at a convergent plate boundary

Explanation:

Hope this helps (:

8 0

3 years ago

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Calculate the speed of a car that has traveled 300 miles in 6 hours.

PilotLPTM [1.2K]

300 miles / 6 hours = 50 miles per hour

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3 years ago

Iron ball sinks in water but not in mercury. Why?

Zigmanuir [339]