List of top Physics Questions on laws of motion asked in DUET

A body of mass $M$ starts sliding down on the inclined plane where the critical angle is $\angle ACB = 30^{\circ}$ as shown in figure. The coefficient of kinetic friction will be
A body of mass $M$ at rest explodes into three pieces, two of them of mass $M/4$ each, are thrown off in perpendicular directions with velocities of $3\, m/s$ and $4 \,m/s$ respectively. The third piece will be thrown off with a velocity of
An iron block of mass $5\, kg$ is kept on a trolley. If the trolley is being pushed with an acceleration of $5\,m / s $$ 2$, what will be the force of friction between the block and the trolley surface? (Take the coefficient of static friction between the block and the trolley surface to be $0,8$).
A person is measuring his weight by standing on a weighing machine inside a lift. When the lift is at rest, the machine shows his weight to be $55 \,kg$. In between the floor when the lift is moving up with a constant speed of $10\, km/h$, he again measures his weight, which is