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loris [4]
2 years ago
10

Someone Help me please

Physics
1 answer:
natali 33 [55]2 years ago
7 0

Answer:

a) Yes because spiderman isn’t part of the system (the train), so he exerts an external force on the system, causing it to slow. The sign is negative because the train is slowing negative.

b) The train was initially moving, so it had kinetic energy, the energy of movement. There isn’t the same amount anymore because spiderman did work onto the train. Work is defined by the change of kinetic energy of the system, so the train didn’t have the same amount of that type of energy at the end.

I hope this helps! :)

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What gravitational force does the earth exert on a person
lara [203]

The  gravitational force exerted by the earth on a person standing on the earth's surface is 602.74 N.

<h3>What is the gravitational force of the earth on the person?</h3>

The gravitational force exerted by the earth on a person standing on the earth's surface is given below as follows:

  • F = \frac{Gm^{1}m^{2}}{r^{2}}

where

G = 6.67 * 10⁻¹¹

m¹ = 62 kg

m² = 5.97 * 10²⁷ kg

r = 6.4 * 10⁶ m

F = \frac{5.97*10^{24}*62*6.67*10^{-11}}{(6.4*10^{6}){2}} = 602.74\:N

Therefore, the gravitational force exerted by the earth on a person standing on the earth's surface is 602.74 N.

Learn more about gravitational force at: brainly.com/question/940770

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2 years ago
Why do people bleed .-.
SashulF [63]
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3 0
3 years ago
Read 2 more answers
An airplane, starting from rest, moves down the runway at constant acceleration for 18 s and then takes off at a speed of 60 m/s
ruslelena [56]

Answer:

a =3.33 m/s²

Explanation:

given,

initial speed of Plane, u = 0 m/s

final speed of plane, v = 60 m/s

time of the acceleration, t = 18 s

average acceleration of the plane, a = ?

average acceleration is equal to change in velocity per unit time.

a = \dfrac{v - u}{t}

a = \dfrac{60 - 0}{18}

a = \dfrac{60}{18}

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Hence, average acceleration of the plane is equal to a =3.33 m/s²

4 0
3 years ago
Read 2 more answers
Early black-and-white television sets used an electron beam to draw a picture on the screen. The electrons in the beam were acce
oee [108]

Answer:

3.25 × 10^7 m/s

Explanation:

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Given that V is the electron speed in m/s

Charge of electron = 1.60217662 × 10-19 coulombs

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3 0
3 years ago
It is believed that increasing amounts of greenhouse gases in the atmosphere will result in
Jobisdone [24]

"Belief" is not involved.  

<em>Choice-A</em> is the correct answer. Except that it's not "... will result in ...".  It's already happening.

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Yes, you can find published researchers who aren't so sure, and who disagree with this conclusion.  The scientific community is <em>never</em> 100% unanimous.  There were reasonable investigators and scientific observers who disagreed with Galileo, Newton, Faraday, Maxwell, Hawking and Einstein, in their time.  

But the voices that dispute human-caused climate change in the form of global warming are few, and they're becoming fewer as time goes on. Today, their reputation sits just a few notches above that of the Flat-Earthers, and it's continuing to sag further.

If we are to do what has to be done, in time to bring about the needed effect, it can't sag fast enough.

8 0
3 years ago
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