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CBSE Class 9 Answered

From top of a building a ball was projected horizontally the ball strikes the ground after 5 seconds at an angle of 60 degree with the horizontal.Calculate the speed with which the ball was projected
Asked by superhero3760 | 27 Jun, 2019, 02:46: PM
answered-by-expert Expert Answer
 
After 5 seconds , vertical component of velocity = (1/2)gt2 = (1/2)×9.8×5×5 = 122.5 m/s
 
if u is projection velocity along horizontal direction at top of building and resultant velocity makes angle 60° with horizontal,
 
then as shown in figure, begin mathsize 14px style fraction numerator begin display style 1 half g t squared end style over denominator u end fraction space equals space tan space 60 space space space space space o r space space space fraction numerator 122.5 over denominator square root of 3 end fraction space equals space u space equals space 70.725 space m divided by s end style
Answered by Thiyagarajan K | 27 Jun, 2019, 07:05: PM

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CBSE 9 - Physics
An object of mass 1kg is falling from the height h=10m.calculate a) the total energy of an object at h=10m b) potential energy of the object when it is at h=4m c) kinetic energy of the object when it is at h=4m d) what will be the speed of the object when it hits the ground
Asked by mailtoparvathyprajith | 08 Feb, 2024, 06:45: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 08 Feb, 2024, 12:32: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 08 Feb, 2024, 12:13: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:50: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:10: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:00: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 08:44: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 06 Feb, 2024, 08:24: PM
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CBSE 9 - Physics
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Asked by sadhanaasadhanaa67 | 04 Feb, 2024, 12:27: PM
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CBSE 9 - Physics
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Asked by mailtoparvathyprajith | 31 Jan, 2024, 06:55: PM
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