contestada

A box of mass 8.0 kg is lifted from the ground and placed on a shelf. The box gains 100J of potential energy. The box falls off the shelf. Air resistance can be ignored. At what speed does the box hit the ground?
A 3.5m/s
B 5.0m/s
C 25m/s
D 28m/s

HELP
​

Respuesta :

kalulesultan

Explanation:

[tex]pe = mgh \: \\ taking \: g \: as \: 10ms^{ - 2} \\ 100 = 8.0 \times 10 \times h \\ h = 1.25m \\ \\ using \: newtons \: third \: equation \\ v^{2} = u^{2} + 2gh \\ where \: v \: is \: final \: velocity \: and \: u \: is \: initial \: velocity \: = 0 \\ v^{2} = 0 + 2 \times 10 \times 1.25 \\ = 25 \\ v = 5.0ms^{2} [/tex]

Otras preguntas