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3 years ago

5

PLEASE HELP!I need help with this

1 answer:

melisa1 [442]3 years ago

3 0

A)

At time = .003 hr

B)

90* (3*10^-3) = .27km

C)

.005 hr

D)

Car A = 150 * (.005) = .75km

Car B = (90 * (.005) = .45 km

E)

Car A = 150 * (0.008) = 1.2 km

Car B = 90 * (0.008) = 0.72 km

Car A is ahead

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A thin rod of length 1.4 m and mass 140 g is suspended freely from one end. It is pulled to one side and then allowed to swing l

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Answer:

a The kinetic energy is $KE = 0.0543 J$

b The height of the center of mass above that position is $h = 1.372 \ m$

Explanation:

From the question we are told that

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The angular speed at the lowest point is $w = 1.09 \ rad/s$

Generally moment of inertia of the rod about an axis that passes through its one end is

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Substituting values

$I = \frac{(0.140) (1.4)^2}{3}$

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$KE = 0.0543 J$

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Answer with Explanation:

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Distance moved by object,d=0.6 m

Spring constant,k=210N/m

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b.

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3 years ago

Starting from zero, the electric current takes 2 seconds to reach half its maximum possible value in an RL circuit with a resist

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Answer:

time=4s

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Applying logarithm on both sides,

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⇒ $log(4)=\frac{t}{\frac{L}{R}}$

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now subs. $\frac{L}{R}=\frac{2}{log2}$

⇒ $t=log4\frac{2}{log2}$

also $log4=log2^{2}=2log2$

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