An electric lift with a maximum load of $2000\,kg$ (lift + passengers) is moving up with a constant speed of $1.5\,m/s$. The frictional force opposing the motion is $3000\,N$. The minimum power delivered by the motor to the lift in watts is: $(g=10\,m/s^2)$

$A$ uniform wooden stick of mass $1.6 \,kg$ and length $l$ rests in an inclined manner on a smooth, vertical wall of height $h$ < $l$ such that a small portion of the stick extends beyond the wall. The reaction force of the wall on the stick is perpendicular to the stick. The stick makes an angle of $30^{\circ}$ with the wall and the bottom of the stick is on a rough floor. The reaction of the wall on the stick is equal in magnitude to the reaction of the floor on the stick. Find the ratio $h/l$ and the frictional force $f$ at the bottom of the stick. $(g=10 \,m \,s^{-2})$

$A$ bullet of mass $0.1\, kg$ is fired into a wooden block to pierce through it,but it stops after moving a distance of $50\, cm$ into it. If the velocity of the bullet before hitting the wood is $10\, m/s$ and it slows down with uniform deceleration,then the magnitude of the effective retarding force on the bullet is $'x'\, N$. The value of $'x'$ to the nearest integer is:

Consider the following statements $A$ and $B$ and identify the correct answer:
$A$. When a person walks on a rough surface,the direction of the frictional force exerted by the surface on the person is in the same direction as his motion.
$B$. When a cycle is in motion,the force of friction exerted by the ground on the front wheel is in the backward direction.

$A$ force $F$ is applied on the top of a cube as shown in the figure. The coefficient of friction between the cube and the ground is $\mu$. If $F$ is gradually increased,the cube will topple before sliding. Then the range of $\mu$ is:

What is the relationship between $W_1$ and $W_2$?