Answer:
The mass of the skateboard is 1.25 kg.
Explanation:
We have,
Mass of dog, m = 5 kg
Initial speed of dog, u = 2.5 m/s
Initial speed of skateboard, u' = 0 (at rest)
The dog jumps onto the skateboard and both the dog and skateboard move with a speed of 2.00 m/s. It is the common speed of the dog +skateboard, V = 2 m/s. We need to find the mass of the skateboard. Using conservation of momentum as :
[tex]mu+m'u'=(m+m')V[/tex]
m' is mass of skateboard
[tex]5\times 2.5=(5+m')2\\\\m'=1.25\ kg[/tex]
So, the mass of the skateboard is 1.25 kg.
