Question

a ball is thrown vertically upward at 20 m/s time taken by ball to return to the thrower's hand is​

Answer 1

Answer:

4 seconds is your answer. I hope it helps.

Answer 2

Answer:

Figure regards,

$\setlength{\unitlength}{1mm}\begin{picture}(7,2)\thicklines\multiput(7,2)(1,0){55}{\line(3,4){2}}\multiput(35,7)(0,4){12}{\line(0,1){0.5}}\put(10.5,6){\line(3,0){50}}\put(35,60){\circle*{12}}\put(37,7){\large\sf{u = 20 m/s}}\put(37,55){\large\sf{v = 0 m/s}}\put(21,61){\large\textsf{\textbf{Ball}}}\put(43,40){\line(0, - 4){28}}\put(43,35){\vector(0,4){18}} {\pmb{\sf{BrainlyButterfliee}}}\put(24, - 3){\large\sf{ \sf g = -9.8 \: m/s^2 }}\put(48,30){\large\sf{T = ?}}\end{picture}$

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Provided that:

• Initial velocity = 20 mps
• Final velocity = 0 mps
• g = -9.8 mps sq.

Don't be confused!

• Final velocity cames as zero because the ball is thrown upwards as it will stop for a while at the highest point.

• We take g as negative because the ball is thrown upwards means against gravity.

To calculate:

• Time taken

Solution:

• Time taken = 2.04 seconds

Using concept:

• First equation of motion

Using formula:

• v = u + at

Where, v denotes final velocity, u denotes initial velocity, a denotes acceleration and t denotes time taken.

Required solution:

»»» v = u + at

»»» 0 = 20 + (-9.8)(t)

»»» 0 - 20 = -9.8t

»»» -20 = -9.8t

»»» 20 = 9.8t

»»» 20/9.8 = t

»»» 2.04 = t

»»» t = 2.04 sec

»»» Time taken = 2.04 sec