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vredina [299]
3 years ago
8

A vector that is 1 cm long represents a displacement of 21 km. How many kilometers are represented by a 3-cm vector drawn to the

same scale?
Physics
1 answer:
koban [17]3 years ago
5 0

The 3 cm vector represents 63 km.

Since a 1 cm long vector represents a displacement of 21 km, we need to find the number of kilometers a 3 cm vector represents.

Let x represent the displacement the 3 cm vector represents.

By ratio, we have 1 cm: 21 km = 3 cm : x

So, 1 cm/21 km = 3 cm/x

Cross-multiplying, we have

x × 1 cm = 3 cm × 21 km

x = 3 cm × 21 km/1 cm

x = 63 km

So, the 3 cm vector represents a displacement of 63 km.

Learn more about displacement here:

brainly.com/question/17673000

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It might be c I'm not sure either. Hope I helped
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rusak2 [61]

Answer:

9.6

Explanation:

to convert km to miles multiply by 1.609

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A proton and an electron are released from rest, with only the electrostatic force acting. Which of the following statements mus
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Answer:

their electrical potential energy decreases. True, because of the negative sign as the distance decreases, it becomes more negative.

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Explanation:

The only force between the proton and the electron is electric

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We can see that it is an attractive force (negative sign)

The electric power energy is

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The kinetic energy is

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With the expressions for each term we can analyze the sentences :

Their electric potential energy increases. False,

their electrical potential energy decreases. True, because of the negative sign as the distance decreases, it becomes more negative.

The kinetic energy increases. True, the force is attractive as the distance decreases the force increases, so acceleration and therefore the speed

Kinetic energy decreases False

The acceleration decreases.  False, as the force increases so does the acceleration

7 0
3 years ago
A child throws a baseball upward with an initial velocity of 20 m/s. The child wants to throw the baseball at least as high as t
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When the ball reaches its maximum height, h, its velocity is zero, so its mechanical energy is just gravitational potential energy:
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for the law of conservation of energy, the initial mechanical energy must be equal to the final mechanical energy, so we have
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From which we find the maximum height of the ball:
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5 0
3 years ago
Is friction and pushing similar ????
olya-2409 [2.1K]

Answer:

Yes, they are.

Explanation:

3 0
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