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luda_lava [24]
3 years ago
12

Mary starts from her house, walks 80 meters south, and stops to chat with her aunt on the sidewalk. After chatting for a few min

utes, she walks 125 meters to the west to meet a friend and then walks 45 meters north with her friend to a cafe for lunch. Overall, she takes 10 minutes to do all this. What is Mary’s average speed?Select one of the options below as your answer: A. 8 meters/second B. 1.25 meters/second C. 25 meters/second D. 4.5 meters/second E. 0.42 meters/second
Physics
1 answer:
marin [14]3 years ago
5 0
Mary walks:
d 1 = 80 m,  d 2 = 125 m,  d 3 = 45 m
t = 10 minutes = 600 seconds;
Average speed:
v = ( d 1 + d 2 + d 3 ) / t 
v = ( 80 m + 125 m + 45 m ) / 600 s
v = 250 m / 600 s
v = 0.4167 m/s ≈ 0.42 m/s
Answer:
E ) 0.42 meters/second
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A student writes, "A bird that is diving for prey has a speed of − 10 m /s ." What is wrong with the student's statement? What h
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Answer:

Speed is a scalar quantity it has only magnitude. So in the given scenario the student actually described about the velocity.

Explanation:

In this situation, student is describing that the speed is -10 m/s. The speed with the negative sign is wrong because speed is a scalar quantity and scalar quantities have only magnitude, they do not have direction. So, his statement is wrong because he is describing the speed with the negative sign.

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3 years ago
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4 years ago
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7 0
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Answer:

8 time increase in K.E.

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