Question

A ball with a mass of 2.3 kg is thrown into the air. If the ball rises to a maximum height of 15 m before stopping and coming back down, how much kinetic energy did the ball have initially?

Answer 1

@harman.singh

Answer 2

http://www.physics.ohio-state.edu/~gan/teaching/spring99/C7.pdf

Answer 3

i just want a formula so i can calculate

Answer 4

KE=0.5*m*v^2

Answer 5

well the formula is given in there if you bothered to read through the entire thing

cliffnotes version

the total energy of the system is composed of potential energy and kinetic energy

TE= KE +PE

Answer 6

what is v

Answer 7

velocity

Answer 8

also, that equation is unnecessary for this problem

Answer 9

If you are asking for explanation, v is the velocity of the ball at a given point

Answer 10

but i am not given a velocity

Answer 11

you dont need to know velocity

Answer 12

I agree with sooobored. You can use the equation they have given you to find the energy

Answer 13

AS I WAS SAYING

kinetic energy is associated with velocity of an object
potential energy is associated with height of the object or displacement of a spring. the latter is unnecessay since there is no spring in this problem

Answer 14

would it be 34.5 j

Answer 15

the gravitational potential energy of an object is represented as
PE= mgh
where m is the mass
g is the gravitational constant 9.81m/s^2
h is the height of the object

Answer 16

we know that at the peak of the objects trajectory(which we consider state 2), it has no speed hence KE=0 but has a whole lot of PE since it is 15m off the ground

Answer 17

338.1 is the pe

Answer 18

We know that at the moment we're about to toss the object up into the air, it has a whole lot of kinetic energy and we assume it has no gravitational potential energy
so the total energy of state 1 would be just be KE

Answer 19

518 J

340 J

52 J

34.5 J
these are my options

Answer 20

now the total energy of systems doesnt change due to conservation of energy
so
KE1 = PE2

Answer 21

since PE1 =0 and KE2=0

Answer 22

since we want to find KE1
and we know PE2= mgh

then KE1=mgh

Answer 23

338.1

Answer 24

guessing the answer doesnt help if you dont know the overall process

Answer 25

2.3 x 9.8 x 15

Answer 26

yes

Answer 27

ok but that isnt any of my choices

Answer 28

After round off, that should become 340J

Answer 29

some people use g=10 m/s^2

Answer 30

ok i have a true or false could yall help me

Answer 31

make another question and ask it there