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A body rravels 200cm in the first 2s and 220 cm in the next 5 s .calculate the velocity at the end of the seventh second from the start.
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A body rravels 200cm in the first 2s and 220 cm in the next 5 s .calcu...
Here is the answerThe displacement of the body in first 2 sec = 200cm Let the initial velocity = u(say) , At t = 0, x(0) = 0, v (0) = u (say), x (t) = 200cm, t = 2s x(t') = (200 + 220)cm = 420cm t' = (2 + 5)s = 7s If a is the uniform acceleration of the particle, then x(t) = x(0) + v(0)t + � at^2 200 = 0 + u*2 + 0.5*a *4 or 100 = u + a ........................................…(1) Again, x(t') = x(0) + v(0)t' + � at^2 420 = 0 + u*7 + 0.5*a*49 60 = u + 3.5a ........................................… (2) Subtracting (1) from (2), -40 = 2.5a or a = -16cm/s2From equation (1), u = 100 - (-16) = 116cm/s Now, t'' = 7s, v(t'') = ? v(t'') = v(0) + at'' v(t'') = (116 - 16*7) = 4cm/s.A body travels 2m in first 2s.Then, 2.2m in next 5s it shows that body is decelerating. So its velocity after 7s could not be 2.22m/s.
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A body rravels 200cm in the first 2s and 220 cm in the next 5 s .calcu...
Calculation of Velocity at the End of the Seventh Second


Given:


  • Distance traveled in the first 2 seconds = 200 cm

  • Distance traveled in the next 5 seconds = 220 cm



Calculating the Average Velocity


The total distance traveled by the body in 7 seconds can be calculated as follows:


Total Distance = Distance in First 2 Seconds + Distance in Next 5 Seconds

Total Distance = 200 cm + 220 cm = 420 cm


The average velocity of the body can be calculated as:


Average Velocity = Total Distance / Total Time

Average Velocity = 420 cm / 7 s = 60 cm/s


Calculating the Final Velocity


Assuming that the body was moving with a constant acceleration, we can use the following equation:


Final Velocity = Initial Velocity + Acceleration x Time


Since the initial velocity is not given, we assume it to be zero.


Let's calculate the acceleration of the body:


Acceleration = Change in Velocity / Time Taken

Acceleration = (Final Velocity - Initial Velocity) / Time Taken

Acceleration = Final Velocity / 7 s


We know that the average velocity of the body is 60 cm/s. We can use this to find the final velocity:


Final Velocity = 2 x Average Velocity - Initial Velocity


Since the initial velocity is zero, we can simplify the equation as:


Final Velocity = 2 x Average Velocity

Final Velocity = 2 x 60 cm/s = 120 cm/s


Conclusion


Therefore, the final velocity of the body at the end of the seventh second from the start is 120 cm/s.
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A body rravels 200cm in the first 2s and 220 cm in the next 5 s .calculate the velocity at the end of the seventh second from the start.
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A body rravels 200cm in the first 2s and 220 cm in the next 5 s .calculate the velocity at the end of the seventh second from the start. for Class 9 2024 is part of Class 9 preparation. The Question and answers have been prepared according to the Class 9 exam syllabus. Information about A body rravels 200cm in the first 2s and 220 cm in the next 5 s .calculate the velocity at the end of the seventh second from the start. covers all topics & solutions for Class 9 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A body rravels 200cm in the first 2s and 220 cm in the next 5 s .calculate the velocity at the end of the seventh second from the start. .
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