Question

Calculate the kinetic energy of a 5.0 kg ball traveling at 6 m/s

Answer 1

\[KE = \frac{ 1 }{ 2 }mv^2\]
You have m and you have v, just plug in and solve.

Answer 2

so im plugging 5.0 times it by 2

Answer 3

No. You're going to put 5 for m, and 6 for v, so what happens is:

\[KE = \frac{ 1 }{ 2 }mv^2 = \frac{ 1 }{ 2 }*5*(6)^2 = \frac{ 1 }{ 2}* 5*36 = = \frac{ 1 }{ 2 }*180 = 90J\]

Answer 4

oh okay i had part of that but thanks can you help me with another one please

Answer 5

Sure, ask away? (BTW, click best response if this helped)

Answer 6

k

Answer 7

J of heat is required to raise the temperature of 100. grams of water by 10. degrees Celsius

Answer 8

---- J of heat is required to raise the temperature of 100. grams of water by 10. degrees Celsius @Zelda

Answer 9

@jmays14, no idea. I have no chem experience. I suggest asking this in the chem subtopic.

Answer 10

k what about this question.....
Calculate the density of an object with a volume of 5.0 cm3 and a mass of 13g

Answer 11

@Zelda

Answer 12

Density = m/v

Answer 13

okay so how would i write it out as a problem to solve

Answer 14

I just told you.

Answer 15

Not much to it mate.

Answer 16

@Zelda

Answer 17

Yes?

Answer 18

how would i write it out as a problem to solve

Answer 19

there is NO problem to solve. DENSITY = M/V = MASS DIVIDED BY VOLUME = MASS/VOLUME.

You just plug into the formula, and evaluate it.

Answer 20

5.0/13

Answer 21

@Zelda

Answer 22

OMG. Honestly mate. Read it again, and again, and again. Even after I spelled it out. you still reversed it.

Answer 23

i didnt revise it you said mass/ volume 13/5.0

Answer 24

Yes, but you put 5/13... Anyhow, yes it is 13/5

Answer 25

okay and i got 2.6 is that correct

Answer 26

If that is what 13/5 is then yes. Sorry for being mad, got slightly frustrated there.

Answer 27

Oh and your units are: g/cm^3

Answer 28

huh now im lost on that one im gonna guess so it'll be 2.6^3= 7.8

Answer 29

No, no no. Basically the unit for density is unit of mass/unit of volume

So your
\[D = 2.6 \frac{ g }{ cm^3 }\]

Answer 30

oh ok do i have to really include that whole problem in my answer i cant just leave it as 2.6

Answer 31

No, you always need units. Otherwise it could be 2.6 elephants!