Here is my question: A 1kg mass undergoes a constant acceleration and when start

Question

Here is my question: A 1kg mass undergoes a constant acceleration and when starting from rest travels 10m in 1 sec. Find the speed of the block at the end of it's first sec, the accerlation of the block, and the force necessary to produce this acceleration.

Now I know that my mass= 1 kg, Vo= Om, V= 10m, t= 1sec

And what I want is: a,speed, Force

The first formula use is to find acceleration right? which is V=Vo + at then you isolate the a to a= V-Vo/ t

which gives me a=10m/ 1 sec or 10m/sec

now i can find my force with F=m(a) which would be F=1kg(10m/sec)

This is where I get lost cause the answer supposed to be 20N. Can anybody help figure out where I might be going wrong or how to get the rest of the answers.

Explanation / Answer

initial velocity = 0

distance travelled = 10m

hence s= 1/2 at^2 gives 10= 1/2 *a(1)

hence acceleration = 20

speed of the block is obtained by using v=u+at

v= 20

force = mass* a=20 N

u took V=10 but its not gifen inthe question that V=10

u may say V=distance/time = 10 but since the body is accelerating u cannot use V= s/time

s=ut is valid only when the body is not acceleratin

general kinematic equatio is s= ut+ 1/2at^2

from this we can get any formula

like u did ,u took acceleration as zero and got s= ut and u=V=10 which is wrong

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