Question

a body of mass 5 kg is thrown vertically upwards with a speed of 10 m/s . what is its kinetic energy when it is thrown ? find its potential energy when it reaches at the highest point ? also find the maximum height attained by the body ..

Answer 1

We have
         m= 5 kg
         v = 10 m/sec
   Hence KE = (1/2)mv²   =  5*10*10 /2   =250 J
Considering Law of conservation of energy - Kinetic energy of the ball will convert into  potential energy when ball reaches the max height.
   Hence we have Potential Energy= 250 J
         let height =h and acceration due to gravity =g= 9.8 m/sec²
         we have PE=250=mgh=5*9.8*h
                                     ⇒h=5.1m
PE is 250J and Max height gained 5.1m

Answer 2

m=5
v=10
ek= 1/2mv^2
   = 1/2*5*10*10=250J
in this case ek =ep
ep=mgh
 250J  = 5*10h
h = 250/50
   = 5 meters.
this ans is also applicable i have asked my teacher