Respuesta :
Answer:
v=3 m/s
Explanation:
the formula for this problem is
V = v 1 ( m 1 / m 1 + m 2 )
we if we substitute ans solve we get this the answer as 3 m/s
Child and stationary skateboard move with same speed, as child jumps onto skateboard. Approximate speed of child and skateboard is 3 m/s.
What is conservation of momentum?
Momentum of a object is the force of speed of it in motion. Momentum of a moving body is the product of mass times velocity.
When the two objects collides, then the initial collision of the two body is equal to the final collision of two bodies by the law of conservation of momentum.
Thus by the law of conservation of momentum,
[tex](m_1u_1)+(m_2u_2)=(m_1+m_2)v[/tex]
Here, [tex]m_1,m_2[/tex] are the masses of two bodies and [tex]u_1,u_2[/tex] are the initial velocities.
Given information-
The mass of the child is 30 kg.
The speed of the child is 10 m/s.
The mass of the skateboard is 10 kg.
Let the speed of the child and skateboard is [tex]v[/tex] m/s.
As the the child and jumps down onto a stationary skateboard then, the speed of child and skateboard should be same.
Thus by the conservation of momentum,
[tex](m_cu_c)+(m_su_s)=(m_c+m_s)v[/tex]
As the initial velocity of the skateboard is 0. Put the values in the above formula as,
[tex](30\times4)+(10\times 0)=(30+10)v\\120+0=40v\\v=3\rm m/s[/tex]
Thus the approximate speed of the child and skateboard is 3 m/s.
Learn more about the conservation of momentum here;
brainly.com/question/7538238
