Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 9 Answered

A particle is moving in a straight line with initial velocity U and uniform accerleration A. if the sum of distances travelled in Tth & (T+1)th second is 100 cm. Then find its velocity after T second in cm/s 
Asked by SIDDHARTH SHARMA | 24 Nov, 2014, 11:08: AM
answered-by-expert Expert Answer
We know that the distance travelled in nth second of uniformly accelerated motion is:
begin mathsize 14px style straight S subscript straight n space equals straight u plus straight a over 2 open parentheses 2 straight n minus 1 close parentheses end style
where u is the initial velocity and a the uniform acceleration of the body.
In this case given that the sum of distances travelled in T th & (T+1) th second is 100 cm
i.e.
S T +S T+1 =100
If the particle is moving with initial velocity U and uniform accerleration A,
Distance travelled by the particle in Tth second can be written as:
begin mathsize 14px style straight S subscript straight T space equals straight U plus straight A over 2 open parentheses 2 straight T minus 1 close parentheses space space space minus minus minus minus minus minus minus minus minus left parenthesis 1 right parenthesis Distance space travelled space by space the space particle space in space open parentheses straight T plus 1 close parentheses to the power of th space second space equals straight S subscript straight T plus 1 end subscript space equals straight U plus straight A over 2 open parentheses 2 open parentheses straight T plus 1 close parentheses minus 1 close parentheses straight S subscript straight T plus 1 end subscript space equals straight U plus straight A over 2 open parentheses 2 straight T plus 1 close parentheses space minus minus minus minus minus minus minus minus left parenthesis 2 right parenthesis Given space that space straight S subscript straight T space plus straight S subscript straight T plus 1 end subscript space equals 100 Substituting space left parenthesis 1 right parenthesis space and space left parenthesis 2 right parenthesis space we space get : straight U plus straight A over 2 open parentheses 2 straight T minus 1 close parentheses space plus straight U plus straight A over 2 open parentheses 2 straight T plus 1 close parentheses space space equals 100 On space solving space we space get : straight U plus AT minus straight A over 2 plus straight U plus AT plus straight A over 2 equals 100 2 straight U plus 2 AT space equals 100 rightwards double arrow straight U plus AT space equals space 50 end style
 
According to the equation of motion, we know that v = u+at
where v is the final velocity, u is the initial velocity, a the acceleration and t the time.
So comparing the equation U+AT =50 with the the equation of motion v= u+at 
we get that the final velocity of the particle at T second  = 50 cm/s
 
 
Answered by Jyothi Nair | 25 Nov, 2014, 09:27: AM

Application Videos

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
CBSE 9 - Physics
The average speed of a moving body can never be zero but the average velocity of a moving body can be zero. Justify.
Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:50: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
  Arrange the following speeds in increasing order(keeping the least speed first): (i) An athlete running with a speed of 10m/s. (ii) An bicycle moving with a speed of 200m/min. (iii) An scooter moving with a speed of 30km/h
Asked by mailtoparvathyprajith | 06 Feb, 2024, 09:10: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
what is motion
Asked by kamalsonkar | 29 Jan, 2024, 11:31: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
when velocity becomes zero
Asked by sapnamantri05 | 24 Nov, 2023, 04:54: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
colliodal example
Asked by ashrithpandu84 | 09 Oct, 2023, 08:09: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
what is derivation
Asked by janhavisoni2099 | 02 Oct, 2023, 05:20: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
If mass of two object is same, than .. a) inertia will be same b) inertia will be different c) momentum will be same. d) momentum will be different
Asked by durgesh21332 | 06 Sep, 2023, 06:17: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
A body moving with uniform acceleration  travels 84m in 6seconds and 264m in 11seconds.  Find acceleration and initial velocity? (In detail)
Asked by sagrawal0081 | 18 Aug, 2023, 05:04: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
question 1) A body is projected vertically upwards from top of the tower with the velocity of 30m/s. if it takes 8sec to reach on ground then what is the height of the tower (g=10ms). what is the total distance travelled by the body. question 2) A body is dropped from the height of h covers by 64% distance in its last second.find out thte total tim of the ball and height. question 3) A body projected vertically upward, At the half  of its maximum height its velocity becomes 20m/s, what is the maximum height attained by the body. question 5) A body is projected vertically upward from ground. the time of flight is 8 sec find the velocity of projection.
Asked by ketkiparasgandhi | 05 Jul, 2023, 08:02: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Physics
define motion provide example of an object in motion  
question image
Asked by leena3732 | 15 Jun, 2023, 09:42: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Get Latest Study Material for Academic year 24-25 Click here
×