Question

A 2kg body and a 3kg body have equal momentum.If the kinetic energy of the 3kg body is 10joules then the kinetic energy of the 2kg body is

Answer 1

Answer:

15 J

Explanation:

M1V1=M2V2

Let m1=2 kg

and m2= 3kg

therefore, 2v1=3v2

now, 1/2 x m2 v2^2= 10 J

then,  v2=√20/3

then, v1= 3/2 x √20/3

v1^2= 9/4 x 20/3=15 ..............(i)

kinetic energy of m1 is 1/2 x m1 v1^2

i.e. 1/2 x 2 x 15= 15 J                     .....(from (i))

Answer 2

Answer:

Explanation:

K.E is inversly proportional to mass

E1/E2=M2/M1

E1/10=3/2

E1=15J

Therfore K.E of 2KG mass is 15J