Which of the diagrams in figure correctly shows the change in kinetic energy of an iron sphere falling freely in a lake having sufficient depth to impart it a terminal velocity?
A cricket ball of mass 150 g moving with a speed of $$126 \mathrm{~km} / \mathrm{h}$$ hits at the middle of the bat, held firmly at its position by the batsman. The ball moves straight back to the bowler after hitting the bat. Assuming that collision between ball and bat is completely elastic and the two remain in contact for 0.001 s , the force that the batsman had to apply to hold the bat firmly at its place would be
A man of mass $$m$$, standing at the bottom of the staircase, of height $$L$$ climbs it and stands at its top.
A bullet of mass $$m$$ fired at $$30^{\circ}$$ to the horizontal leaves the barrel of the gun with a velocity $$v$$. The bullet hits a soft target at a height $$h$$ above the ground while it is moving downward and emerge out with half the kinetic energy it had before hitting the target.
Which of the following statements are correct in respect of bullet after it emerges out of the target?
Two blocks $$M_1$$ and $$M_2$$ having equal mass are free to move on a horizontal frictionless surface. $$M_2$$ is attached to a massless spring as shown in figure. Initially $$M_2$$ is at rest and $$M_1$$ is moving toward $$M_2$$ with speed $$v$$ and collides head-on with $$M_2$$.
