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3 years ago

A rock hits the ground with a speed of 13 m s−1

Physics

1 answer:

polet [3.4K]3 years ago

4 0

Answer:

3.55kg

Explanation:

K. E = ½mv²

Where m = mass, v = velocity

K. E = 300J

v = 13m/s

Therefore,

K. E = ½mv²

300 = ½ × m × 13²

Multiply both sides by 2

600 = m × 169

Divide both sides by 169

m = 600 ÷ 169

mass = 3.55kg

I hope this was helpful, please mark as brainliest

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Softa [21]

Chemical energy.

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3 years ago

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An icicle falls off of a skyscraper from rest and falls for 34 seconds. How fast will that icicle be moving after that time? Sho

goblinko [34]

Answer:

<em>The icicle will be moving at 333.54 m/s</em>

Explanation:

<u>Free Fall Motion </u>

A free-falling object falls under the sole influence of gravity. Any object that is being acted upon only by the force of gravity is said to be in a state of free fall. Free-falling objects do not encounter air resistance.

If an object is dropped from rest in a free-falling motion, it falls with a constant acceleration called the acceleration of gravity, which value is $g = 9.81 m/s^2$ .

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vf = 9.81*34

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3 years ago

A coin is made of ______

lys-0071 [83]

Answer:

coins made with the combination of copper zinc and Nickel

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3 years ago

A car goes from rest to a speed of 90 km/h in 10 seconds . What is the car's acceleration in m/s²

zloy xaker [14]

First you must convert Km/hr to m/s. 90 km/hr equals 25m/s (this can be done through a conversion table by plugging in the conversion values). Then you need to see what was given:
vi (initial velocity)= 0m/s
vf (final velocity= 25m/s (90km/hr)
t (time)= 10s

Next you should find an equation that requires only the values you know and gives you the value you're looking for. Sometimes that requires two equations to be used, but in this case you only need one. The best equation for this would be a=(vf-vi)/t. Finally, plug in your values (a=(25-0)/10) to get your answer which would be 2.5m/s^2. Hope this helped!

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3 years ago

Once you start pulling your object with less force than friction, what should you expect your object to do? What about when your

forsale [732]

#Case -1

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#Case-2

If Pulling force is greater than frictional force then object will be .

In order to calculate friction force you need Limiting friction first .

$\\ \sf\longmapsto F_L=\mu sN$