Question

.A force of 5N changes the velocity of abody from 10

m/s to 20m/s in 5 sec. How much force is required to bring

about the same change in 2 sec ?​

Answer 1

Answer:

We know,

At    t=nsec

s  

n

​  

=  

2

1

​  

an  

2

 

v  

2

=2as  

n

​  

       

      =2a⋅  

2

1

​  

an  

2

       

       =a  

2

n  

2

     

∴v=an

∴a=  

n

v

​  

      ...(i)

Now,     s  

n

​  

−s  

n−2

​  

=  

2

1

​  

a[n  

2

−(n−2)  

2

]                

=  

2

1

​  

a[4n−4]                

=2a(n−1)              from (i)

s  

n

​  

−s  

(n−2)

​  

=  

n

2v(n−1)

​

Explanation: