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galben [10]
3 years ago
5

A bus travels 300 km south along a straight path with an average velocity of 85 km/h to the south. The bus stops for 22 minutes.

Then it travels 220 km south with an average velocity of 78 km/h to the south. How long does the total trip last? What is the average velocity for the total trip?
Physics
1 answer:
Kruka [31]3 years ago
5 0

a) Answer;

= 6.72 hours

Explanation and solution;

velocity = distance over time  

Since we know the velocity and the distance, we can simply calculate time  

For the first part  

85 km/h = 300km / time  

time = 3.53 hours  

Then there is a 22 min stop, which is the same as 0.37 hours  

so far the trip is:  

3.53 + 0.37 = 3.9 hours  

then for the last stretch:  

78 km/h = 220 km / time  

time = 2.82 hours  

So the total trip is:  

3.9 + 2.82  = 6.72 hours

b) Answer;  

=  77.38 km/hr

Explanation and solution;

we take the total distance divided by the total time to get the average.  

total distance = 300 km + 220 km = 520 km  

total time = 6.72 hours  

Average velocity = 520 km / 6.72 hours =  77.38 km/hr


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Answer:

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b) 13.35*10^6 V

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V=k[\frac{q_1}{r_1}+\frac{q_2}{r_2}]\\\\V=(8.98*10^9Nm^2/C^2)[\frac{3.90*10^{-6}C}{0.0125m}+\frac{-2.4*10^{-6}C}{0.018m}]=1.6*10^6V

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b) For the coordinate (1.50 cm , 0) = (0.015 m, 0) you have:

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A force of 48 newtons is required to start a 5.0 kg box moving across a horizontal concrete floor. What is the coefficient of st
Soloha48 [4]

1) The coefficient of static friction is 0.980

2) The coefficient of kinetic friction is 0.908

Explanation:

1)

In the first situation, the box is still at rest. There are two forces acting on the box:

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- The force of static friction, F_f

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