Question

answer this question plz​

Answer 1

$\huge\mathfrak\red{Answer}$

POINT TO REMEMBER

WHEN A BODY IN TRANSLATIONAL MOTION MOVE WITH CERTAIN VELOCITY HAVE TRANSLATIONAL KINETIC ENERGY BUT WHEN THE SAME BODY MOVE SUCH THAT THE MOTION IS IN BOTH TRANSLATIONAL OR ROTATIONAL THAN THE KINETIC ENERGY IS NOT EQUALS TRANSLATIONAL KINETIC ENERGY BUT THIS BODY HAVE BOTH TRANSLATIONAL KINETIC ENERGY AS WELL AS ROTATIONAL KINETIC ENERGY.

$\\mass = 100kg \\ velocity = 20cm {sec}^{ - 1} = 0.2m {sec}^{ - 1} \\ \\ translational \: kinetic \: energy = \frac{1}{2} m {v}^{2} \\ translational \: kinetic \: energy = \frac{1}{2} (100)(0.04) \\ translational \: kinetic \: energy = 2joules \\ \\ moment \: of \: inertia(i) = m \frac{ {r}^{2} }{2} \\ moment \: of \: inertia = \frac{1}{2} \times 100 \times 4 \\ moment \: of \: inertia = 200kg {m}^{2} \\ \\ rotational \: kinetic \: energy = \frac{1}{2} i {( \frac{v}{r} )}^{2} \\ rotational \: kinetic \: energy = \frac{1}{2} \times 200 \times \frac{0.2 \times 0.2}{2 \times 2} \\ rotational \: kinetic \: energy = 1joules \\ \\ total \: kinetic \: energy = 1 + 2 = 3joules \\ \\ work \: done \: to \: stop \: the \: disc = 3joules$