A ball is thrown horizontally from a cliff at a speed of 10 m/s. Calculate its speed one second later.?

14 milimeters per millisecond

Take g = 9.81 m/s²
Along the vertical direction, take all downward quantities as positive.

Along the horizontal direction, the ball in uniform speed motion.
Horizontal component of the speed 1 s later = 10 m/s

Along the vertical direction :
v = u + at
v = 0 + 9.81 × 1
v = 9.81 m/s

Speed one second later
= √(10² + 9.81²)
= 14 m/s

Horizontal:

Horizontal Acceleration always = 0.
Horizontal Initial velocity= 10m/s

Vertical:

Acceleration = 9.8 (acceleration due to gravity)
Initial velocity = 0
Final velocity = ??
Time = 1
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Using the equation: Final Velocity = Initial Velocity + acceleration x time
Final Velocity = 0 + 9.8 x 1
Final velocity = 9.8m/s.