Question

When non-conservative forces do work, energy is transformed from kinetic to potential (or vice versa), but:

Option 1: Total mechanical energy is conserved
Option 2: Total mechanical energy is lost
Option 3: Mechanical energy is not affected
Option 4: Energy is converted to thermal energy

Answer 1

When non-conservative forces do work, total mechanical energy is lost as it is converted to other forms such as thermal energy.

Step-by-step explanation:

When non-conservative forces do work, energy is transformed from kinetic to potential (or vice versa). However, mechanical energy may not be conserved when nonconservative forces act. For example, when a car is brought to a stop by friction on level ground, it loses kinetic energy, which is dissipated as thermal energy, reducing its mechanical energy.

The correct option is Option 2: Total mechanical energy is lost. When nonconservative forces do work, energy is converted to other forms such as thermal energy, so the total mechanical energy is not conserved.