1.) At one point in its fall, an object (m=2.5 kg.) has a kinetic energy of 5 J(joule) and a potential energy of 10 J.

Question

1.) At one point in its fall, an object (m=2.5 kg.) has a kinetic energy of 5 J(joule) and a potential energy of 10 J.

a) what is the total energy of the system?

b) what is the velocity at this point?

The object continues to another point where its potential energy is 3J(joule).

c) what is the KE(kinetic energy) at this point.

d) what is the velocity at this point.

e)how high off of the ground is the object.

>> FORMULAS <<
KE=1/2 v^2
PE= mgh

_please help me! >.<

1 answer

a) E(total) =KE+PE=5+10 =15 J
b) v=sqrt(2•KE/m)=…(m/s)
c) KE1=15 -3 =12 J
d) v1=sqrt(2•KE1/m)=…(m/s)
e) PE= mgh = 3J
h=3/mg=3/2.5•9.8=.... (m)

Elena · Answer

a) E(total) =KE+PE=5+10 =15 J b) v=sqrt(2•KE/m)=…(m/s) c) KE1=15 -3 =12 J d) v1=sqrt(2•KE1/m)=…(m/s) e) PE= mgh = 3J h=3/mg=3/2.5•9.8=.... (m)