Question

29. A particle moves in plane with acceleration
ā=2i+2j. If the initial velocity of particle is
v=3i+6j then final velocity of particle at time
t=2s is
(1) 5i+8j
(2) 7i +10j
(3) 2i +6j (4) 3i + 2j​

Answer 1

a=v (final)- v (initial)/time

2i+2j=v(final)-(3i+6j)/2

v(final)-(3i+6j)=(2i+2j)×2

=4i+4j

v(final)=4i+4j+3i+6j

=7i+10j

option 2 is the answer

Answer 2

Answer:

2)7i + 10j

Explanation:

acceleration is equal to change in velocity per total time time taken

acc= final velocity (v) - initial velocity (u )/ total time

total time (t) = 2s

initial velocity = 3i +6j

acc= 2i +2j

let final velocity be as x

substitute the values ,

2i+2j = x - [3i+6j ] /2

after solving u will get x = 7i + 10 j