A2.0 kg pendulum has an initial total energy of 20 j. calculate the energy lost as heat if the pendulum is 0.10 m high and is traveling at 4.0 m/s. a) 2.0j b) 18j c) 14j d)16j

The correct answer is (A) 2.0 J

Total energy of the pendulum is the sum of its kinetic and potential energy. At the instant of time, when the pendulum is at a height h and has a speed v, Its energy is given by,

Substitute 2.0 kg for m, the mass of the pendulum, 9.81 m/s² for g, the acceleration due to gravity, 0.10 m for h and 4.0 m/s for v.

The pendulum has an initial energy of 20 J. the energy lost is given by,

Thus, the energy lost by the pendulum is (A) 2.0 J

the independent variable, the one that is intentionally manipulated, is whether or not the car hits the barrier.

the dependent variable, the one that you measure the response in, is the distance that the washers travel.