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Aleks [24]
3 years ago
13

A skier has an acceleration of 2.5 m/s2. How long does it take her to come to a complete stop from a speed of 18 m/s?

Physics
2 answers:
Andrej [43]3 years ago
8 0
A = 2.5 m/s²

since , we have to stop so v = 0 m/s ( final velocity)

u = 18 m/s

t = ?

using ,

⇒ v = u + at

⇒ 0 = 18 + 2.5t

by this we are getting t<0 , since , t cant be -ve , Check your question
aleksandr82 [10.1K]3 years ago
4 0
(Assuming acceleration is -2.5m/s2) 7.2 seconds.
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By re-arranging this equation, we can find V_i:
V_i =  \frac{nRT_i}{p_i} = \frac{(2.3 mol)(8.31 J/mol K)(513 K)}{1.01 \cdot 10^5 Pa}=0.097 m^3

2) Now the gas cools down to a temperature of
T_f = 14^{\circ}C=287 K
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3) In a process at constant pressure, the work done by the gas is equal to the product between the pressure and the difference of volume:
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by using the data we found at point 1) and 2), we find
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3 years ago
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sergiy2304 [10]

Answer:

h = 4 in

Explanation:

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we know that

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16 = r^2 h

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Answer:

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