An element's atomic number is 58. How many protons would an atom of this element have?

How do I do this physics problem about potential energy and kinetic energy?

larisa86 [58]

Ok i apologise for the messy working but I'll try and explain my attempt at logic

Also note i ignore any air resistance for this.

First i wrote the two equations I'd most likely need for this situation, the kinetic energy equation and the potential energy equation.

Because the energy right at the top of the swing motion is equal to the energy right in the "bottom" of the swing's motion (due to conservation of energy), i made the kinetic energy equal to the potential energy as indicated by Ek = Ep.

I also noted the "initial" and "final" height of the swing with hi and hf respectively.

So initially looking at this i thought, what the heck, there's no mass. Then i figured that using the conservation of energy law i could take the mass value from the Ek equation and use it in the Ep equation. So what i did was take the Ek equation and rearranged it for m as you can hopefully see. Then i substituted the rearranged Ek equation into the Ep equation.

So then the equation reads something like Ep = (rearranged Ek equation for m) × g (which is -9.81) × change in height (hf - hi).

Then i simplify the equation a little. When i multiply both sides by v^2 i can clearly see that there is one E on each side (at that stage i don't need to clarify which type of energy it is because Ek = Ep so they're just the same anyway). So i just canceled them out and square rooted both sides.

The answer i got was that the max velocity would be 4.85m/s 3sf, assuming no losses (eg energy lost to friction).

I do hope I'm right and i suppose it's better than a blank piece of paper good luck my dude xx

4 0

3 years ago

A 25 kg block is held against a compressed spring and then the spring is allowed to decompress giving the block a velocity. The

Alex787 [66]

Answer:

h=18.05 cm

Explanation:

Given that

m= 25 kg

K= 1300 N/m

x=26.4 cm

θ= 19.5 ∘

When the block just leave the spring then the speed of block = v m/s

From energy conservation

$\dfrac{1}{2}Kx^2=\dfrac{1}{2}mv^2$

$Kx^2=mv^2$

$v=\sqrt{\dfrac{kx^2}{m}}$

By putting the values

$v=\sqrt{\dfrac{kx^2}{m}}$

$v=\sqrt{\dfrac{1300\times 0.264^2}{25}}$

v=1.9 m/s

When block reach at the maximum height(h) position then the final speed of the block will be zero.

We know that

$V_f^2=V_i^2-2gh$

By putting the values

$0^2=1.9^2-2\times 10\times h$

h=0.1805 m

h=18.05 cm

4 0

3 years ago

If the volume on your TV is low, turning the volume up one click of the remote control will make the TV seem louder than if the

marusya05 [52]

From what we know, we can confirm that this ratio (turning up the volume by one click relative to the TV's overall volume) can be quantified as the Weber fraction.

<h3>What is the Weber fraction?</h3>

This fraction describes the ratio needed for change to a stimulus in which the change is just barely noticeable. This question is a prime example in that it seeks to find out just how low of a difference is needed in TV volume in order for the difference to be noticeable.

Therefore, we can confirm that this ratio (turning up the volume by one click relative to the TV's overall volume) can be quantified as the Weber fraction.

To learn more about Weber visit:

brainly.com/question/5004433?referrer=searchResults

7 0

2 years ago

Calculating the Mass of a Granite Monument

Volgvan

Answer:

m = 684,865,8 g

Step-by-step explanation

V = 25,365.4 cm^3 Is volume

r = 27g/cm^3 Is density

To calculate mass you use formula:

m= V*r

m = 25,365.4 x 27

m = 684,865,8 g

8 0

2 years ago

There is less oxygen in air at higher altitudes than at sea level. Scientists have shown that people living at sea level have 5

Ivanshal [37]

Answer with Explanation:

"Red Blood Cells" (RBCs) contain Hemoglobin that is responsible for carrying oxygen into the body. When people are exposed to higher altitudes, the number RBCs in the body increases. This is because the body has a hard time taking in oxygen due to low atmospheric pressure. It makes it hard for oxygen to pass through the lung membranes. This is called "hypoxia." Such condition deprives the body from oxygen, thus, it creates more red blood cells in order to compensate the condition.

When it comes to people living at sea level, the oxygen can easily pass through the lung membranes due to higher atmospheric pressure. This doesn't require the body to build new RBCs. Therefore, the numbers of RBCs needed by people to thrive is lower than living at higher altitudes.

5 0

3 years ago