Question

a particle starts moving from rest with uniform acceleration of 5 m/s^2 for 10s and then it moves witha constant velocity

Answer 1

You can use the formula:

and here we can use only 2nd eqution of velocity bcz according to 1st and 3rd velocity constant then we can find nothing so

we will use

s=ut+1/2at^2

where s=distance travelled

u=initial velocity

a=acceleration

t=time

According To Question,

u=0m/s(as the body starts from rest, thus it's obvious that the initial velocity will be 0),t=10s, a=5m/s^2, s=?

Now put the value in the formula:

s = ut+1/2at^2

s = 0(10s)+ 1/2(5m/s^2)(10s)^2

s = 0+1/2(5m/s^2)(100s^2)

s= 1/2 x 5 x 100 = 250 m

i hope it will help you 

regards