JEE Class main Answered
a body covers 200cm in first 2sec and 220 cm in next 4sec with deceleration velocity of the body at the end of seventh second is
Asked by chinnarisharanya1979 | 16 May, 2021, 01:45: PM
Expert Answer
From the given information , we consider that the object starts from rest and
accelerated for 2 seconds and has travelled 200 cm in accelerated motion
Acceleration a is detrmined from the equation , S = (1/2) a t2 ,
where S is the distance covered in t seconds
200 = (1/2) a × 2 × 2 , hence we get a = 100 cm/s2 .
velocity after 2 seconds = a × t = 100 × 2 = 200 cm/s
It is given that for next 4 seconds the object has travelled 220 cm with deceleration ar .
We get deceleration ar from the relation , S = ( u t ) - [ (1/2) ar t2 ]
220 = ( 200 × 4 ) - [ (1/2) × ar × 4 × 4 ]
8 ar = ( 220 - 800 ) = 580 or ar = 72.5 cm/s2
After 6 seconds if deceleration continues , then velocity v after 7 seconds is determined as
( deceleration has started after 2 seconds from starting time and after initial velocity 200 cm/s )
v = u - ( ar t ) = 200 - ( 72.5 × 5 ) = -162.5 cm/s
Answered by Thiyagarajan K | 16 May, 2021, 02:55: PM
JEE main - Physics
Asked by Machinenineha | 27 Mar, 2024, 05:28: PM
ANSWERED BY EXPERT
JEE main - Physics
Asked by tripathiji9876good | 10 Jan, 2024, 04:22: PM
ANSWERED BY EXPERTJEE main - Physics
Asked by meenu0000156 | 05 Jan, 2024, 12:05: PM
ANSWERED BY EXPERT
JEE main - Physics
Asked by joanmaria916 | 17 Jul, 2023, 11:24: AM
ANSWERED BY EXPERTJEE main - Physics
Asked by theavengers0203 | 22 May, 2023, 11:54: PM
ANSWERED BY EXPERT
JEE main - Physics
Asked by khushpatel9579 | 16 Feb, 2023, 07:50: PM
ANSWERED BY EXPERTJEE main - Physics
Asked by yadavashishkryadav | 13 Jan, 2023, 08:38: AM
ANSWERED BY EXPERT
