A cheetah, weighing 150 kg, chases a deer, weighing 30 kg, in a straight path. The speed of the cheetah is 20 m / s and that of the deer is 25 m / s. The approximate speed of the centre of mass of the pair is

Question

A cheetah, weighing 150 kg, chases a deer, weighing 30 kg, in a straight path. The speed of the cheetah is 20 m / s and that of the deer is 25 m / s. The approximate speed of the centre of mass of the pair is (A) 21 m/s (B) 24 m/s (C) 26 m/s (D) zero

Tardigrade Admin · Accepted Answer

Velocity of the centre of mass vC M=(m1 v1+m2 v2/m1+m2) =((150 × 20)+(30 × 25)/150+30) =(3750/180)=21 m / s

Q. A cheetah, weighing $150 k g$ , chases a deer, weighing $30 k g$ , in a straight path. The speed of the cheetah is $20 m / s$ and that of the deer is $25 m / s$ . The approximate speed of the centre of mass of the pair is

21 m/s

24 m/s

26 m/s

zero

Velocity of the centre of mass
$v_{CM} = \frac{m _{1} v _{1} + m _{2} v _{2}}{m _{1} + m _{2}}$
$= \frac{( 150 \times 20 ) + ( 30 \times 25 )}{150 + 30}$
$= \frac{3750}{180} = 21 m / s$

Q. A cheetah, weighing 150kg, chases a deer, weighing 30kg, in a straight path. The speed of the cheetah is 20m/s and that of the deer is 25m/s. The approximate speed of the centre of mass of the pair is