Question

a boat of mass 60kg is at rest . A dog of mass 6kg moves in a boat with velocity 15 m/s what is the velocity of the boat nearly

Answer 1

Given : a boat of mass 60kg is at rest .

A dog of mass 6kg moves in a boat with velocity 15 m/s

To Find :   velocity of the boat

Solution:

m = mass of dog  =  6 kg

M = Mass of Boat = 60 kg

Total mass in Boat = mass of dog + Mass of Boat  = 6 + 60 = 66 kg

v = velocity of Dog = 15 m/s

V = Velocity of Boat

Apply conservation of momentum

mv  + (M + m)V = 0

=> 6(15) + ( 60 + 6)V = 0

=> 90 + 66V = 0

=> V = -90/66

=> V = -15/11

=> V = -1.36 m/s

-ve sign indicates that velocity of boat is in opposite direction.

velocity of the boat = 1.36 m/s in opposite direction

Learn More:

A boat which can move with a speed of 5 m/s relative to water ...

https://brainly.in/question/10630334

A boy of mass 36 kg moves from one end to other end of a boat of ...

https://brainly.in/question/31010562

Answer 2

Given :

• Aboat of mass 60kg is at rest .
• A dog of mass 6kg moves in a boat with velocity 15 m/s

To Find :   velocity of the boat ?

Solution:

1. m = mass of dog  =  6 kg
2. M = Mass of Boat = 60 kg

Total mass in Boat = mass of dog + Mass of Boat   ‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎

‎ ‎ ‎ ‎‎ ‎ = 6 + 60

‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎= 66 kg

and,

‎v = velocity of Dog = 15 m/s

V = Velocity of Boat

Apply conservation of momentum

‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎mv  + (M + m)V = 0

‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎=> 6(15) + ( 60 + 6)V = 0

‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎=> 90 + 66V = 0

‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎=> V = -90/66

‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎=> V = -15/11

‎ ‎ ‎‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎=> V = -1.36 m/s

( -ve sign indicates that velocity of boat is in opposite direction. )

Hence, velocity of the boat = 1.36 m/s in opposite direction