Need help with hw momentum and collisions

In summary, The conversation is discussing the maximum recoil speed of the Earth when a person jumps straight up, assuming the Earth is a solid object. The solution should state the physical quantities used as data and their corresponding values. The answer is estimated to be around 10^-23 m/s, keeping in mind that the common center of mass remains at rest at all times. The mass times velocity of the person must equal the mass times velocity of the Earth, but with opposite sign to maintain a total of 0.
  • #1
ballahboy
34
0
i hav no clue how to do this problem...

How fast can you set the Earth moving? In particular, when you jump straight up as high as you can, you give the Earth a maximum recoil speed of what order of magnitude? Visualize the Earth as a perfectly solid object. In your solution state the physical quantities you take as data and the values you measure or estimate for them.

Can anyone help me with this?
btw, the answer should be about 10^-23m/s
 
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  • #2
Remember that your common center of mass remains at rest at all times..
 
  • #3
Your mass times velocity must equal the Earth's mass time velocity (but with opposite sign in order that the total remain 0.
 

1. What is momentum in physics?

Momentum is a fundamental concept in physics that describes the quantity of motion an object has. It is a vector quantity, meaning it has both magnitude and direction, and is calculated by multiplying an object's mass by its velocity.

2. How is momentum conserved in collisions?

According to the law of conservation of momentum, the total momentum of a closed system remains constant before and after a collision. This means that the total momentum of the objects involved in the collision will be the same before and after the collision, regardless of any external forces acting on the system.

3. What is the difference between elastic and inelastic collisions?

In an elastic collision, both kinetic energy and momentum are conserved, meaning that the objects involved bounce off each other without losing any energy. In an inelastic collision, some kinetic energy is lost due to deformation or heat, and only momentum is conserved.

4. How do you calculate the velocity of an object after a collision?

The velocity of an object after a collision can be calculated using the conservation of momentum equation: m1v1 + m2v2 = m1v1' + m2v2', where m represents mass and v represents velocity. By rearranging the equation, you can solve for the final velocity of either object involved in the collision.

5. How is momentum related to force?

Momentum and force are related through Newton's second law of motion, which states that force is equal to the rate of change of momentum. In other words, the greater the force applied to an object, the greater the change in its momentum will be.

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