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3 years ago

How much work is done in accelerating a 2000 kg car from rest to a speed of 30 m/s?

1 answer:

8 0

The work done is the same as the amount of energy increase. The formula for kinetic energy is 122
1
2
m
v
2
.

The initial KE of the car is 12(1000)×202=200,000
1
2
(
1000
)
×
20
2
=
200
,
000
joules.

The final KE of the car is 12(1000)×302=450,000
1
2
(
1000
)
×
30
2
=
450
,
000
joules.

The difference between these is the amount of work done: 450,000−200,000=250,000
450
,
000
−
200
,
000
=
250
,
000
joules.
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steposvetlana [31]

Answer:

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Unchanged

Decreased

Explanation:

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7 0

3 years ago

A geosynchronous Earth satellite is one that has an orbital period of precisely 1 day. Such orbits are useful for communication

koban [17]

Answer:

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Explanation:

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Learn more about thermal power here: brainly.com/question/7541718

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