A strip of wood of mass M and length l is placed on a smooth horizontal surface. An insect of mass m starts at one end of the strip and walks to the other end in time t, moving with a constant speed.

Options

A. The speed of the insect as seen from the ground is `lt (1)/(t)`
B. The speed of the strip as seen from the ground is `(1)/(l) ((M)/(M+m))`
C. The speed of the strip as seen from the ground is `(1)/(l) ((m)/(M+m))`
D. The total kinetic energy of the system is `(1)/(2) (m+M) ((1)/(t))^(2)`

Answer

A, C