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Grade 12th PassGeneral Physics

A ball is thrown upward and caught by the thrower after 8 seconds.How below the highest point was it 5 seconds from the start?
  • 1m
  • 4.9m
  • 9.8m
  • 19.6m
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Profile image of ASh
8 Years agoGrade 12th Pass
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1 Answer

Profile image of Arun
ApprovedApproved Tutor Answer8 Years ago

8 second here indicates the total time taken by the ball to reach highest point and come back to the thrower. So the highest point is reached at half the time i.e. 4 seconds. take g=9.8m/s^2

v=u-gt (since ball goes upward)

at highest point v=0, time taken=4

u=v+gt

u=39.2m/s…….

v^2=u^2-2gh (ball goes upward)

at highest point v=0

h=u^2/2g

h=78.4m……..(highest point)

h=ut- .5gt^2

t=5 seconds, u=39.2

h=196 - 0.5 *9.8 *25

h = 73.5

so your answer would be= 78.4–73.5= 4.9m