1) Two identical cars have the same speed, one traveling east and one traveling

Question

1) Two identical cars have the same speed, one traveling east and one traveling west. Do the cars have the same momentum? Explain

2) You have a choice. You may get hit head-on by either an adult moving slowly on a bicycle or by a child that is moving twice as fast on a bicycle. The mass of the child is one-half that of the adult on the bicycle. Which collision do you prefer? Account for your answer.

3) When you are driving a golf ball, a good follow-through helps to increase the distance of the drive. A good follow-through means that the club head is kept in contact with the ball as long as possible. Why does this technique allow you to hit the ball farther?

4) A satellite explodes in outer space, far from any other body, sending thousands of pieces in all directions. How does the linear momentum of the satellite before the explosion compare with the total linear momentum of all the pieces after the explosion? Account for your answer.

5)Which has greater momentum, a 2.0kg hockey puck moving east at 2.5m/s or a 1.3kg hockey puck moving south at 3.0m/s?

Explanation / Answer

Ans: - 1] If the identical car have the exact mass

since p=mv by this formula their momentum is to be a same &t heir velocity are already same

2]collision is doesn’t matter it depends on mass and velocity

Impact is means p = m*v ……………………..for adult

For child impact is = (m/2)*2*v = m * v

So adult is going slowly impact is same

3]by using impulse momentum theorem

to maximize change in momentum of ball, which results in a higher ball speed, the impulse of the golf club against the ball must be maximized

Impulse = Favg*time

Favg = (avg tangential acceleration ) *mass of ball

For a given golfer the Favg is constant or nearly so, then the impulse can be maximized by increasing time.

time = length of time ball is in contact with golf club, ie the time of "follow thrugh" must be maximized.

4]The momentum before and after explosion is same so there is no external force acting on satellite by law of conservation of motion

By Newton’s second law

F = m*a

Acceleration = delta v/ delta t

F*delta t = m*delta v =change in momentum

Change in momentum = 0 …….no external force

So momentum before and after is same

5] P1 = m*v = 2*2.5 = 5kgm/s

P2 = m*v = 1.3*3 = 3.9kgm/s

P1>P2

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.