Question

Question no 12 please help me

Answer 1

Ans1. (1) AB part of graph shiw accelarated motion...
(2) Cd part of the graph show retarded motion...
(3)8m

STEP BY STEP EXPLANATION


(1) As we see that the AB part is going suddenly upwards with respect to time so there is change in velocity per unit time...and to find whether it us accelarating or retarding...we have to see the graph. If it goes upwards then it means there is positive accelaration and if we see it going downwards it is negative accelaration or retardation.

(2)by watching the graph go down with say that CD part of the graph is read negative acceleration because it is going downwards also for more information check my answer 1 and between the two books that it is explained


(3)for finding the distance covered by the body in 4 second we need to find the area of triangle ABE and to find the area of triangle ABE here foloows,,.....
$ar= 1 \div 2 \: base \times height$
$that \: is \: \: 1 \div 2 \times 4 \times 4$

because time is base and height is the velocity of body at the same heigt as pount B

So

$1 \div 2 \times 4 \times 4 = 2 \times 4 = 8m$
that is the dustance covered