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3 years ago

A car slow down at -5.00 m/s2 until it comes to a stop after traveling 15.0 m. What was the initial speed of the car? (Unit=m/s)

Physics

2 answers:

sp2606 [1]3 years ago

8 0

Answer:

12.25 m/s

Explanation:

If a car slows down at -5 m/s2 and it comes to a stop after traveling 15 m we just have to use the next formula:

$Vf^{2} =Vo^{2} +2ad$

Now we know that the final velocity is 0, so by inserting our data into the formula it would look like this:

$Vf^{2} =Vo^{2} +2ad$

$0 =Vo^{2} +2(-5m/s^{2})(15m)$

$-Vo^{2}= -150m^{2}/s^{2}$

$Vo^{2}= 150m^{2}/s^{2}$

$Vo= \sqrt{150m^{2}/s^{2}}$

$Vo= 12.25m/s$

vlabodo [156]3 years ago

7 0

Good formula to remember!

V_F^2 = V_0^2 + 2 * a * d

V_F = final speed
V_0 = initial speed

0^2 = V_0^2 + 2*(-5)*15 = V_0^2 -150,

V_0 = sqrt(150) = 12.25 m/s

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Here,

$f_0$ = Frequency of Source

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3 years ago

A heavy anvil is suspended by a 0.75 m long steel wire that has a mass of 12 g. When the wire is plucked, it hums at its fundame

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Explanation:

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$f=\dfrac{v}{2l}$

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$\mu$ is the mass per unit length, $\mu=\dfrac{m}{l}$

$f=\dfrac{1}{2l}\sqrt{\dfrac{T}{\mu}}$

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3 years ago

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n200080 [17]

Answer

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