CBSE Class 11-science Answered

Velocity of truck after 10 sec = 2x10 = 20 m/s²

When stone is released, it'll also have the same velocity.  So the stone has a horizontal velocity of 20 m/s²

Time required to reach ground = (2h/g) = (12/9.8) = 1.11 sec.

So it'll reach ground at 11.11 sec.

Horizontal velocity remains unchanged, Vx = 20.

Vertical velocity = ut+0.5gt² = 0.5x9.8x1² = 4.9 m/s²

Velocity of stone = (Vx²+Vy²) =(20²+4.9²) = 20.6 m/s² and an angle tan^-1(4.9/20) with the horizontal.

The acceleration will always be g = 9.8 m/s²

Regards,

Team,

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