Q.

If the velocity of a particle is v=At+Bt2, where A and B are constants, then the distance travelled by it between 1 s and 2 s is:        [2016]

1 32A+73B  
2 A2+B3  
3 32A+4B  
4 3A+7B  

Ans.

(1)

Velocity of the particle is v=At+Bt2

dsdt=At+Bt2; ds=(At+Bt2)dt    s=At22+Bt33+C

s(t=1s)=A2+B3+C;  s(t=2s)=2A+83B+C

Required distance=s(t=2s)-s(t=1s)

=(2A+83B+C)-(A2+B3+C)=32A+73B