2.2.12 Conservation of linear momentum / Newton's 3rd Law

1. Why does a gangstah (note new spelling) not actually fly back through a glass window when he "takes" a bullet

The bullet is travelling too fast

He might will be wearing a bullet proof vest

The total momentum before he is it is too small to make a significant change in his velocity

The bullet gives all the momentum to the person that fired the bullet.

The correct answer is that the total momentum before he is hit is too small to make a significant change in his velocity. This means that the gangster's body is not able to absorb enough momentum from the bullet to cause him to fly back through a glass window.

Explanation

The correct answer is that the total momentum before he is hit is too small to make a significant change in his velocity. This means that the gangster's body is not able to absorb enough momentum from the bullet to cause him to fly back through a glass window.

2. According to newton's 3rd Law, If I push a car forward,

The car will accelerate slowly

The car will move at constant velocity

The car will not move at all

The car will push me back

I have been taking too many high energy drinks.

According to Newton's third law of motion, for every action, there is an equal and opposite reaction. When you push a car forward, you are applying a force on the car. As a result, the car will push back on you with an equal and opposite force. This is why the correct answer is "the car will push me back." The acceleration or movement of the car is not mentioned in the question, so it is not relevant to the answer. The reference to high energy drinks is unrelated and does not affect the outcome described by Newton's third law.

Explanation

According to Newton's third law of motion, for every action, there is an equal and opposite reaction. When you push a car forward, you are applying a force on the car. As a result, the car will push back on you with an equal and opposite force. This is why the correct answer is "the car will push me back." The acceleration or movement of the car is not mentioned in the question, so it is not relevant to the answer. The reference to high energy drinks is unrelated and does not affect the outcome described by Newton's third law.

3. If the gangstah stands on the pavement, which are newton's third law pair of forces

The gansta pushes down on the ground, and the ground pushes up on the gansta (reaction)

The earth pulls down on the gangster, and the pavement pushes up on the ganster

The ganster's mass pulls up on the earth, and the ground pushes up on the gangster.

When the gangsta stands on the pavement, the force exerted by the gangsta pushing down on the ground is the action force. According to Newton's third law, there is always an equal and opposite reaction force. In this case, the reaction force is the ground pushing up on the gangsta. This pair of forces follows Newton's third law, where the action and reaction forces are equal in magnitude and opposite in direction.

Explanation

When the gangsta stands on the pavement, the force exerted by the gangsta pushing down on the ground is the action force. According to Newton's third law, there is always an equal and opposite reaction force. In this case, the reaction force is the ground pushing up on the gangsta. This pair of forces follows Newton's third law, where the action and reaction forces are equal in magnitude and opposite in direction.

4. Which is the best wording to describe the conservation of momentum

Momentum before a collision is the same as the momentum after the collision

Momentum before a collision is the same as the momentum after the collision if there are no external forces

The total momentum before a collision is equal to the total momentum after a collision

The best wording to describe the conservation of momentum is that the total momentum before a collision is equal to the total momentum after the collision if the total external forces acting upon the system is zero. This means that in a closed system where no external forces are acting, the total momentum of the system remains constant before and after a collision.

Explanation

The best wording to describe the conservation of momentum is that the total momentum before a collision is equal to the total momentum after the collision if the total external forces acting upon the system is zero. This means that in a closed system where no external forces are acting, the total momentum of the system remains constant before and after a collision.

5. In explosion type collision, two static trolleys of masses 2Kg and 3Kg start to move apart (pushed by a spring between them), What is the velocity of the first trolley if the 3Kg trolley moves with velocity 4m/s?

3m/s

-3 m/s

4 m/s

-4 m/s

6 m/s

-6 m/s

In an explosion type collision, the two trolleys move apart from each other after being pushed by a spring. The momentum of the system is conserved, which means that the total momentum before the collision is equal to the total momentum after the collision. Since the 3Kg trolley moves with a velocity of 4m/s, the momentum of the system after the collision is (3Kg * 4m/s) + (2Kg * v), where v is the velocity of the 2Kg trolley. Since the total momentum before the collision is zero (since the trolleys are initially static), the total momentum after the collision must also be zero. Solving the equation (3Kg * 4m/s) + (2Kg * v) = 0, we find that v = -6m/s.

Explanation

In an explosion type collision, the two trolleys move apart from each other after being pushed by a spring. The momentum of the system is conserved, which means that the total momentum before the collision is equal to the total momentum after the collision. Since the 3Kg trolley moves with a velocity of 4m/s, the momentum of the system after the collision is (3Kg * 4m/s) + (2Kg * v), where v is the velocity of the 2Kg trolley. Since the total momentum before the collision is zero (since the trolleys are initially static), the total momentum after the collision must also be zero. Solving the equation (3Kg * 4m/s) + (2Kg * v) = 0, we find that v = -6m/s.