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2 years ago

9

The engine in an imaginary sports car can provide constant power to the wheels over a range of speeds from 0 to 70 miles per hou

r (mph). At full power, the car can accelerate from zero to 29.0 mph in time 1.10 s .A more realistic car would cause the wheels to spin in a manner that would result in the ground pushing it forward with a constant force (in contrast to the constant power in Part A). If such a sports car went from zero to 29.0 mph in time 1.10 s , how long would it take to go from zero to 58.0 mph ?

1 answer:

bekas [8.4K]2 years ago

6 0

Answer:

2.2 seconds

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration

Converting mph to m/s

$29\ mph=29\times 0.44704=12.96\ m/s$

$58\ mph=58\times 0.44704=25.93\ m/s$

$v=u+at\\\Rightarrow a=\frac{v-u}{t}\\\Rightarrow a=\frac{12.96-0}{1.1}\\\Rightarrow a=11.78\ m/s^2$

Considering this acceleration to be constant

$v=u+at\\\Rightarrow t=\frac{v-u}{a}\\\Rightarrow t=\frac{25.93-0}{11.78}\\\Rightarrow t=2.20\ s$

Time it would take to go from zero to 58.0 mph is 2.2 seconds

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Two small aluminum spheres, each of mass 0.0250 kilograms, areseparated by 80.0 centimeters.

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1 year ago

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Answer:

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Explanation:

Part a

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Here

$\gamma_d$ is the dry unit weight which is to be calculated
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Part c

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Degree of Saturation is given as

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G is the specific gravity which is given as 2.72

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Substituting values

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Part d

Additional Water needed

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Here

$\gamma_{zav}$ is the zero air unit weight which is to be calculated

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w is the moisture content in percentage, given as 12% or 0.12 in fraction

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