Apendulum is constructed from a 5.9 kg mass attached to a strong cord of length 1.6 m also attached to a ceiling. originally hanging vertically, the mass is pulled aside a small distance of 7.1 cm and released from rest. while the mass is swinging the cord exerts an almost-constant force on it. for this problem, assume the force is constant as the mass swings. how much work in j does the cord do to the mass as the mass swings a distance of 8.0 cm?

Work done is zero

Solution:

As per the question:

Mass of the pendulum, m = 5.9 kg

Length of the cord, l = 1.6 m

Distance moved by the mass, x = 7.1 cm = 0.071 m

Now,

To calculate the work done when the displacement of the mass is 8 cm:

Work done is given by the formula:

W =

Also, we know that in simple pendulum, the force due to the string reamins perpendicular to the displacement of the mass from the mean position.

Thus

Therefore, the work done is zero.

car stops. he keeps going = he has inertia

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