Question

the accelerationof a body is 9.8 m/s^2. what do u understand by the statement?

Answer 1

It means, if you let a body fall freely (on earth), then this is the rate at which it will gain in speed towards the ground. It's called the acceleration due to gravity. Which in turn means, suppose you let a rock fall from the top of a really tall building. It's speed will change as follows:

after 1 sec - 9.81 m/s
after 2 secs - 19.62 m/s
after 3 secs - 29.43 m/s
.
.
.

In newtonian gravitation, the force of gravity between two bodies is given by Fm1m2=Gm1m2r2Fm1m2=Gm1m2r2, where m1m1 and m2m2 are the masses, r is the separation between them, and G is a constant. Since the radius of the earth is a pretty large value, we may safely ignore the effect of changes in r when performing our experiments close to the surface of the earth. So, g = 9.81 m/s is an accurate enough value for most numerical problems.

Personally, I use g = 10 m/s because 9.81 is just makes the calculations too involved.
so this is correct statement....I hope you like it.....click as a brilliant plz

Answer 2

1-. x-t graph of body must be parabolic
2-body may be falling freely from the point above the ground as g=9.8 m/s²
3-its motion is accelerated