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2 years ago

7

If a vector that is 3cm long represents 30 km/h, what velocity does a 5 cm long vector which is drawn using the same scale repre

sent?
A.50 km/h
B. 60 km/h
C. 100 km/h

1 answer:

poizon [28]2 years ago

5 0

Answer: A. 50 km/h

Explanation:

3 * 10 = 30

5 * 10 = 50

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Answer:

The range of powers is $- 5 \ D \le P \le - 2.667\ D$

Explanation:

From the question we are told that

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From these parameter we can see that with the glass on that for near point the

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converting to meters

$f = - \frac{75}{2} * \frac{1}{100}$

$f = - \frac{75}{200} \ m$

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Substituting values

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From these parameter we can see that with the glass on that for far point the

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substituting values

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Answer:

That is, mechanical waves cannot travel through a vacuum. This feature of mechanical waves is often demonstrated in a Physics class. A ringing bell is placed in a jar and air inside the jar is evacuated. Once air is removed from the jar, the sound of the ringing bell can no longer be heard.

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