Question

a body of mass 2 kg has initial velocity of 3m/s along x axis and it is subjected to a foce of 4 n in y direction the displacemnet of body from origin after 4 seco ds will be( the body was subjected to force at the origin at t=0)

Answer 1

Find displacements separately in x and y directions., Now find resultant of the two.
Hope it helps!!

Answer 2

The displacement of body is 20 m.

Solution:

We name the force vector pulling the block upwards as OA and that to the side as OE.

Therefore, along OA

We know that, by second law of motion,  

$F=m a$

$\Rightarrow a=\frac{\text {Force}}{\text {Mass}}=\frac{4}{2}=2 \ \mathrm{m} / \mathrm{s}^{2}$

$u=0 \ m / s$

$t=4 s$

Using the equation of motion and substituting the values,

$s=u t+\frac{a t^{2}}{2}=0+\left(2 \times \frac{4 \times 4}{2}\right)=16 \ m$

Along OE

$u=3 \ m / s$

$a=0 \ m / s^{2}$

$s=u t=3 \times 4=12 \ m$

$OE=\sqrt{162+122}=20 \ \mathrm{m}$