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fiasKO [112]
3 years ago
9

Suzanne bikes 3 km to school every day. it takes her 20 minutes because she always has to stop at a traffic light. what is her a

verage speed?
a. 0.15 km/s
b. 3 m/s
c. 6.7 km/minute
d. 9 km/h
Physics
1 answer:
masha68 [24]3 years ago
3 0
3 km in 20 min => 9 km in 60 min => 9km in 1h =>
 the correct answer is d: 9 km/h


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When a board with a box on it is slowly tilted to larger and larger angle, common experience shows that the box will at some poi
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What is the minimal mass of helium (density 0.18 kg/m3) needed to lift a balloon carrying two people in a basket, if the total m
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 ==================================== 
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3 0
3 years ago
A transparent oil with index of refraction 1.28 spills on the surface of water (index of refraction 1.33), producing a maximum o
Ad libitum [116K]

Answer:

The thickness of the oil slick is 1.95\times10^{-7}\ m

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t = \dfrac{1\times\times500\times10^{-9}}{2\times1.28 }

t=1.95\times10^{-7}\ m

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Answer:                  

32 amu is the right choice because both protons and neutrons have a mass of 1 amu. Electrons have no mass so go with the last choice

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