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3 years ago

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A rock weighing 98 newtons is pushed off the edge of a bridge 50 meters above the ground. What was the potential energy of the r

ock before it began to fall?

2 answers:

barxatty [35]3 years ago

5 0

<u>Answer:</u> The potential energy of the rock before it began to fall is 4900 J

<u>Explanation:</u>

Force is defined as the mass multiplied by the acceleration of the object.

$F=mg$

where,

F = force exerted on the object

m = mass of the object

g = acceleration due to gravity

Potential energy is defined as the energy possessed due to the height of the object.

Mathematically,

$E_p=mgh$

Or,

$E_p=F\times h$

where,

$E_p$ = potential energy of the rock = ?

F = force applied on the rock = 98 N

h = height of the bridge from where the rock is thrown = 50 m

Putting values in above equation, we get:

$E_p=98N\times 50m\\\\E_p=4900J$

Hence, the potential energy of the rock before it began to fall is 4900 J

lidiya [134]3 years ago

4 0

Ep = 4900 because Ep = wh

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2 years ago

A commuter airplane starts from an airport and takes theroute. The plane first flies to city A, located 175 km away in a directi

bearhunter [10]

Answer:

245.45km in a direction 21.45° west of north from city A

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Let's place the origin of a coordinate system at city A.

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The module of this position is:

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And the angle measure from the y-axis is:

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So the answer is 245.45km in a direction 21.45° west of north from city A

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3 years ago

According to the intuitive guess you just made, is the overall momentum of the two-cart system after the collision greater than,

Aloiza [94]

Answer:

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3 years ago

You need to repair a gate on the farm. The gate weighs 100 kg and pivots as indicated. A small diagonal bar supports the gate an

tekilochka [14]

Answer:

The force is $F = 3920 \ N$

Explanation:

The diagram for this question is shown on the first uploaded image

From the question we are told that

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From the diagram , taking moment about the pivot we have

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3 years ago

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Marianna [84]

Answer:

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$v=\frac{\Delta s}{\Delta t}$

However, we can see that this definition corresponds to the slope of the curve in a position-time graph. In fact:

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So, the velocity is

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which corresponds to the slope of the curve.

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3 years ago

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