2. A 50.0 kg shell was fired from a cannon at earth's surface to a
maximum height of 400. m.
a. What is the potential energy at maximum height?
b. It then fell to a height of 100. m. What was the loss of PE as
it fell?

Respuesta :

Answer: a) 196000 Joules

b) 147000 Joules

Explanation:

a. Potential energy is the energy possessed by an object by virtue of its position.

[tex]P.E=m\times g\times h[/tex]

m= mass of object = 50.0 kg

g = acceleration due to gravity = [tex]9.8ms^{-2} [/tex]

h = height of an object = 400 m

Putting in the values we get:

[tex] P.E=50kg\times 9.8ms^{-2}\times 400m=196000kgm^2s^{-2}=196000Joules[/tex]     [tex](1kgm^2s^{-2}=1Joule )[/tex]

Thus the potential energy at maximum height is 196000Joules.

b. [tex] P.E=50kg\times 9.8ms^{-2}\times 100m=49000kgm^2s^{-2}=49000Joules[/tex]     [tex](1kgm^2s^{-2}=1Joule )[/tex]

Thus loss in P.E = (196000Joules-49000Joules) = 147000 Joules