Hey!
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Answer:
Substance
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Explanation:
Water is a substance created with oxygen and hydrogen.
A mixture is when more than one substance are mixed together.
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Hope This Helped! Good Luck!
Explanation:
We'll call the radius r and the diameter d:
We also assume that the riders are at a distance r = d/2 = 7m from the center of the wheel.
The period of the wheel is 24s. The tangent velocity of the wheel (and the riders) will be: (2pi/T)*r = 0.8 m/s (circa).
It means that in 3 minutes (180 seconds) they'll run 0.8 m/s * 180s = 144m.
Hopefully I understood the question. If yes, that's the answer.
Answer:
The approximate change in entropy is -14.72 J/K.
Explanation:
Given that,
Temperature = 22°C
Internal energy 
Final temperature = 16°C
We need to calculate the approximate change in entropy
Using formula of the entropy

Where,
= internal energy
T = average temperature
Put the value in to the formula


Hence, The approximate change in entropy is -14.72 J/K.
Answer:
Explanation:
Given
mass of sled =26 kg
coefficient of static friction 
coefficient of kinetic friction 
In order to move sled from rest we need to provide a force greater than static friction which is given by

After Moving Sled kinetic friction comes in to play which is less than static friction

therefore minimum force to keep moving sledge at constant velocity is 18.34 N
Answer:
The maximum mass that can fall on the mattress without exceeding the maximum compression distance is 16.6 kg
Explanation:
Hi there!
Due to conservation of energy, the potential energy (PE) of the mass at a height of 3.32 m will be transformed into elastic potential energy (EPE) when it falls on the mattress:
PE = EPE
m · g · h = 1/2 k · x²
Where:
m = mass.
g = acceleration due to gravity.
h = height.
k = spring constant.
x = compression distance
The maximum compression distance is 0.1289 m, then, the maximum elastic potential energy will be the following:
EPE =1/2 k · x²
EPE = 1/2 · 65144 N/m · (0.1289 m)² = 541.2 J
Then, using the equation of gravitational potential energy:
PE = m · g · h = 541.2 J
m = 541.2 J/ g · h
m = 541.2 kg · m²/s² / (9.8 m/s² · 3.32 m)
m = 16.6 kg
The maximum mass that can fall on the mattress without exceeding the maximum compression distance is 16.6 kg.