PLease answer this question or explain

A ball with a mass of 3kg is dropped from the top of a building this is 20m high. what is the velocity of the ball when it is 10

anzhelika [568]

Answer:

Velocity=14[m/s]

Explanation:

We can solve this problem by using the principle of energy conservation, where potential energy becomes kinetic energy.

In the attached image we can see the illustration of the ball falling from the height of 20 meters, at this time the potential energy will have the following value.

$Ep=m*g*h\\where:\\m=3[kg]\\h=20[m]\\$

$Ep=3*9.81*20\\Ep=588.6[J]$

When the ball passes through half of the distance (10m) its potential energy will have decreased by half as shown below.

$Ep=3*9.81*10\\Ep=294.3[m]$

If we know that potential energy is transformed into kinetic energy, we can find the value of speed.

$Ek=\frac{1}{2} *m*v^{2} \\therefore\\v=\sqrt{\frac{Ek*2}{m} } \\v=\sqrt{\frac{294.3*2}{3} } \\\\v=14[m/s]$

7 0

4 years ago

Papers scattered randomly across the desk represents high entropy and are a good example of which law?

lord [1]

<span>The second law of thermodynamics states that the entropy of any isolated system always increases.

So the paper tends to approach high entropy

Answer is C</span>

8 0

4 years ago

Calculate the average times it took the car to travel 0. 25 and 0. 50 meters. Record the averages, to two decimal places, in Tab

Illusion [34]

The average speed of the given car is 2.22 s and 3.13 s for 0.25 m and 0.50 m distance respectively.

<h3>How to calculate the Average speed?</h3>

The average speed can be calculated by adding the speed of each trial divided by the number of trials,

For 0.25 m the average speed will be:

$S_{avg} = \dfrac{2.24 + 2.21 + 2.23}{ 3}\\\\S_{avg} = 2.22$

For the 0.50 m, the average speed will:

$S_{avg} = \dfrac {3.16 + 3.08 + 3.15} {3 }\\\\S_{avg} = 3.13\rm \ s$

Therefore, the average speed of the given car is 2.22 s and 3.13 s for 0.25 m and 0.50 m distance respectively.

Learn more about Average speed:

brainly.com/question/26386984

6 0

3 years ago

Sprinting near the end of a race, a runner with a mass 63 kg accelerates from a speed of 25 m/s to a speed of 26 m/s in 54 s. To

gavmur [86]

Answer:

1.1655 N

Explanation:

Given that,

Initial speed, u = 25 m/s

Final speed, v = 26 m/s

Time taken, t = 54 s

So, Applying equation of motion as:

$v=u+at\\\Rightarrow a=\frac{v-u}{t}\\\Rightarrow a=\frac{26-25}{54}\ m/s^2\\\Rightarrow a=0.0185\ m/s^2$

According to the Newton's second law of motion:-

$Force=Mass\times Acceleration$

Mass = 63 kg

So,

$Force=63\times 0.0185\ kgm/s^2$

<u>Force = 1.1655 N</u>

5 0

4 years ago

Which of the following is true about density and states of matter for most substances?

anyanavicka [17]

<u><em>The right answer is "A) Substance is denser as a solid than as a gas" Trust me I just got it wrong because of this guy down here or girls not trying to judge</em></u>

4 0

3 years ago