Question

The force an a particle of mass 10 gm is $(10\hat{i}=5\hat{J}$N).It starts from rest, what would be its position at time t = 5 seconds.

Answer 1

Given, $m=10gm=0.01kg$ And $F=10\hat{i}+5\hat{j}$

So, Using $F=ma$

Acceleration in $x-direction=1000m/s$

And using second equation of motion $s=ut++\frac{1}{2}a{t}^2$

Displacement in $x-direction$ after 5 secs $0\left(5\right)+\frac{1}{2}\times 1000\times 5^2=12500\hat{i}$

Now, Acceleration in $y-direction=500m/s$

And using second equation of motion again $s=ut++\frac{1}{2}a{t}^2$

Displacement in $y-direction$ after 5 secs $0\left(5\right)+\frac{1}{2}\times 500\times 5^2=6250\hat{j}$

So , its position at time t = 5 seconds $=12500\hat{i}+6250\hat{j}$