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from the edge of a roof you throw a snowball downward that strikes the ground with 100J of kinetic energy. then you throw a second snowball upward with the same initial speed, and this too falls to the ground. neglecting air resistance, the second snowball hits the ground with a kinetic energy of:
a. 100J
b. 200J
c. more than 200J
d. less than 200J
e. none of the above

Respuesta :

Answer:

The second snowball hits the ground with a kinetic energy of 100 Joules

Explanation:

Given that,

From the edge of a roof you throw a snowball downward that strikes the ground with 100 J of kinetic energy. It is a case of conservation of energy.

At the highest point,

[tex]mgh+\dfrac{1}{2}mu^2=mgh'+0[/tex]          

[tex]100=mgh'[/tex]

At lowest point,

[tex]mgh'=K[/tex]

From above two equation, we get :

Kinetic energy, K = 100 J

So, the second snowball hits the ground with a kinetic energy of 100 Joules. So, the correct option is (A).