Non-conservative Forces — MCQ Practice

Which of the following statements about non-conservative forces is INCORRECT?

A $0.5\,\text{kg}$ block slides $2\,\text{m}$ down a rough inclined plane that makes an angle of $37^\circ$ with the horizontal. If the coefficient of kinetic friction is $0.25$, what is the work done by friction during this motion? (Take $g = 10\,\text{m/s}^2$, $\sin37^\circ = 0.6$, $\cos37^\circ = 0.8$)

A $4\,\text{kg}$ block is initially at rest on a rough horizontal surface. A horizontal force of $20\,\text{N}$ is applied to the block. If the coefficient of kinetic friction is $0.2$, what is the speed of the block after it has moved $5\,\text{m}$? (Take $g = 10\,\text{m/s}^2$)

A $1\,\text{kg}$ block slides down a $37^\circ$ incline of length $5\,\text{m}$. If it starts from rest and reaches the bottom with a speed of $6\,\text{m/s}$, what is the work done by friction? ($g=10\,\text{m/s}^2$, $\sin37^\circ = 0.6$, $\cos37^\circ = 0.8$)

An object of mass $5\,\text{kg}$ falls from rest through a height of $10\,\text{m}$. If it reaches the ground with a speed of $10\,\text{m/s}$, what is the work done by air resistance during its fall? (Take $g = 10\,\text{m/s}^2$)

A $200\,\text{kg}$ car is moving at a constant speed of $20\,\text{m/s}$ on a horizontal road. If the total resistive force (friction and air resistance) acting on the car is $500\,\text{N}$, what is the power dissipated by these non-conservative forces?

A block of mass $m$ is pulled up a rough inclined plane (angle $\theta$) by a constant force $F$ parallel to the incline. If the coefficient of kinetic friction is $\mu_k$, and the block moves a distance $d$, which expression correctly represents the work done by all non-conservative forces?