1). Walking / Driving
If there were no static friction between the soles of your shoes and the ground, then you could move your feet back and forth but your body would never go anywhere.
Same for using tires to move a car, a bus, a bicycle or a motorcycle.
2). Sleeping
If there were no static friction between your jammies and the sheet, you would slide right off of the bed whenever there was the slightest breeze of air in the room.
The final velocity of the block A will be 2.5 m/sec. The principal of the momentum conversation is used in the given problem.
<h3>What is the law of conservation of momentum?</h3>
According to the law of conservation of momentum, the momentum of the body before the collision is always equal to the momentum of the body after the collision.
In a given concern, mass m₁ is M, mass m₂ is 3M. Initial speed for the mass m₁ and m₂ will be u₁=5 and u₂=0 m/s respectively,
According to the law of conservation of momentum
Momentum before collision =Momentum after collision
m₁u₁+m₂u₂=(m₁+m₂)v
M×5+3M×0=[M+3M]v
The final velocity is found as;
V=51.25 m/s
The velocity of block A is found as;

Hence, the final velocity of the block A will be 2.5 m/sec.
To learn more about the law of conservation of momentum, refer;
brainly.com/question/1113396
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Answer:
Picture
Explanation:
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