The bob (weight) at the end of a pendulum has a mass of 0.3 kilograms. The bob is pulled to position B and allowed to swing. It
goes all the way to position C and swings back.
The potential energy of the bob at position B is >>1.47 joules. If the maximum height of the bob is 0.45 meters when it swings back, ___ joules of energy was transformed to thermal energy.
>>>>>Use g = 9.8 m/s2 and PE = m × g × h.<<<<<
It's NOT 1.323!!!
The potential energy of the bob at position B is >>1.47 joules. If the maximum height of the bob is 0.45 meters when it swings back, ___ joules of energy was transformed to thermal energy.
>>>>>Use g = 9.8 m/s2 and PE = m × g × h.<<<<<
It's NOT 1.323!!!
1 answer:
Answer:
0.147 J
Explanation:
The total energy that has been transformed into thermal energy is equal to the loss of gravitational potential energy between the initial situation (bob at h=0.5 m above the ground) and the final situation (bob back but at h=0.45 m above the ground).
Therefore, we have
where
m = 0.3 kg is the mass of the bob
g = 9.8 m/s^2
h1 = 0.5 m is the initial height
h2 = 0.45 m is the final height
Substituting, we find the thermal energy
Therefore, the energy transformed into thermal energy is 0.147 J.
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