Question

Two bodies with moment of inertia i1 and i2 have equal angular momentum

Answer 1

1.

we know that kinetic energy of rotation is given as

E = (1/2)Iw

as L = Iw, we have

E = (1/2)L.w..........................(1)

now, we are given that angular momenta of two bodies are equal

L = L

or

I w = I w

so,

I / I = w / w .....................(2)

now as I > I

I / I > 1

or from (2)

w / w > 1

thus,

w > w

now,

for body 1

E = (1/2)L.w

and

for body 2

E = (1/2)L.w

as

w > w we get  

E > E

or

E < E

hence proved.

..

2.

Relation between Torque (τ) and Angular Momentum (L) is given as

τ = dL/dt

here,

dL = 2 J.s

dt = 5s

so,

τ = 2/5  = 0.4 Nm

thus, correct answer is option (d)

Answer 2

Please complete the question what to do??