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3 years ago

Use the GUESS method to solve the problem below.

Physics

1 answer:

pochemuha3 years ago

8 0

Answer:

2.75 m

Explanation:

Given that,

Little baby bird drops the worm and sadly watches it fall to the ground below in 0.75 seconds.

We need to find how high is the nest. Let it is h. It can be calculated using second equation of motion as follows :

$h=ut+\dfrac{1}{2}at^2$

Here, u = 0 and a = g

$h=\dfrac{1}{2}gt^2\\\\h=\dfrac{1}{2}\times 9.8\times (0.75)^2\\\\h=2.75\ m$

So, the nest is 2.75 m high.

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A racecar driver is driving her car down the drag strip at 120 m/s. What is the shortest distance in which she can brake and sto

DaniilM [7]

Answer:

1034.78 m

Explanation:

The shortest distance is the displacement of the car from initial position to final position.

Displacement of body is given using Newton's equations of motion.

Given:

Initial velocity, $u = 120$ m/s

Final velocity, $v = 0$ m/s( As the car stops in its final position)

Coefficient of static friction, $\mu=0.71$

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Now, when brakes are applied, only friction acts on the body in a direction opposite to that of its motion.

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Plug in 0.71 for $\mu$ and 9.8 m/s² for $g$ . Solve for $a$ .

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$v^{2}=u^{2} +2aS$

Here, $S$ is the displacement of the racing car.

Plug in 120 m/s for $u$ , 0 m/s for $v$ , -6.958 m/s² for $a$ . Solve for $S$ . This gives,

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4 years ago

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3 years ago

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Answer:

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