Physics Homework Question due in 20mins, literally have no idea what i'm doing

In summary: Where m1 and m2 are the masses of the two objects, v1 and v2 are their initial velocities, and v1' and v2' are their final velocities.We can plug in the given values for mass and velocity, and the known final velocity for the composite system:(1/2 * 4.72 kg * v1^2) + (1/2 * m2 * 0) = (1/2 * 4.72 kg * (v1/3)^2) + (1/2 * m2 * (v1/3)^2)Simplifying, we get:(4.72 kg * v
  • #1
Jrlandshark
2
0
014 (part 1 of 2) 10.0 points

A(n) 19 g object moving to the right at
24 cm/s overtakes and collides elastically with
a 34 g object moving in the same direction at
14 cm/s.

Find the velocity of the slower object after
the collision.

Answer in units of cm/s.



015 (part 2 of 2) 10.0 points

Find the velocity of faster object after the
collision.

Answer in units of cm/s.



016 10.0 points

A(n) 4.72 kg sphere makes a perfectly in-
elastic collision with a second sphere that is
initially at rest. The composite system moves
with a speed equal to one-third the original
speed of the 4.72 kg sphere.

What is the mass of the second sphere?

Answer in units of kg.
 
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  • #2


Hello! Let's work through these questions together.

First, we need to find the velocity of the slower object after the collision. To do this, we can use the conservation of momentum principle, which states that the total momentum of a system remains constant before and after a collision. In this case, we can write the equation:

(m1 * v1) + (m2 * v2) = (m1 * v1') + (m2 * v2')

Where m1 and m2 are the masses of the two objects, v1 and v2 are their initial velocities, and v1' and v2' are their final velocities.

We can plug in the given values for mass and velocity:

(19 g * 24 cm/s) + (34 g * 14 cm/s) = (19 g * v1') + (34 g * v2')

Solving for v1', we get:

v1' = (19 g * 24 cm/s + 34 g * 14 cm/s) / (19 g + 34 g)

v1' = 19.83 cm/s

Therefore, the slower object will have a final velocity of 19.83 cm/s after the collision.

Next, we can use the same equation to find the velocity of the faster object after the collision. We just need to plug in the new values for v1' and v2':

(19 g * 24 cm/s) + (34 g * 14 cm/s) = (19 g * v1') + (34 g * v2')

Solving for v2', we get:

v2' = (19 g * 24 cm/s + 34 g * 14 cm/s) / (19 g + 34 g)

v2' = 34.17 cm/s

Therefore, the faster object will have a final velocity of 34.17 cm/s after the collision.

Moving on to the third question, we need to find the mass of the second sphere. To do this, we can use the conservation of kinetic energy principle, which states that the total kinetic energy of a system remains constant before and after a collision. In this case, we can write the equation:

(1/2 * m1 * v1^2) + (1/2 * m2 * v2^2) = (1/2 * m1 * v1'^2) + (
 
  • #3




As a scientist, it is important to approach problems with a systematic and logical mindset. In this situation, it is important to first identify the relevant information and equations that can be used to solve the problem. In this case, we can use the conservation of momentum and conservation of kinetic energy equations to solve for the velocities and masses of the objects involved in the collisions.

For the first question, we can use the equation m1v1 + m2v2 = m1v1' + m2v2', where m1 and v1 are the mass and velocity of the first object before the collision, m2 and v2 are the mass and velocity of the second object before the collision, and v1' and v2' are the velocities of the objects after the collision. We know the masses and velocities of both objects before the collision, so we can plug in these values and solve for v2' to find the velocity of the slower object after the collision.

For the second question, we can use the same equation, but this time we are solving for v1' to find the velocity of the faster object after the collision.

For the third question, we can use the equation (m1 + m2)v = m1v1 + m2v2, where v is the velocity of the composite system and v1 and v2 are the velocities of the individual objects. We know the mass and velocity of the composite system and the mass and velocity of one of the objects, so we can solve for the mass of the second object.

Remember to always double check your units and make sure they are consistent throughout the calculations. Also, it is important to show your work and explain your reasoning in order to receive full credit for the homework. Good luck!
 

1. What is the best approach to solving a physics homework question?

The best approach to solving a physics homework question is to break it down into smaller, manageable parts and use the relevant formulas and concepts that you have learned in class. It is also important to carefully read and understand the question, and to double check your work for any errors.

2. How can I improve my understanding of the subject to better complete my homework?

One way to improve your understanding of physics is to actively engage in class, take thorough notes, and ask questions when you are unsure about something. Additionally, practicing more problems and seeking help from a tutor or teacher can also be beneficial.

3. I have no idea where to start with my physics homework. What should I do?

If you have no idea where to start, it is important to first review the relevant concepts and formulas that are needed to solve the problem. You can also try breaking the problem down into smaller parts and tackling them one at a time. If you are still struggling, don't hesitate to seek help from a teacher or tutor.

4. Can I use a calculator for my physics homework?

Yes, you can use a calculator for your physics homework. However, it is important to understand the concepts and formulas involved in the problem before relying on a calculator. In some cases, you may also be required to show your work and not just the final answer.

5. Is it important to show all of my work in a physics homework question?

Yes, it is important to show all of your work in a physics homework question. This not only helps you to check your own work for errors, but it also allows your teacher or tutor to see your thought process and provide feedback on any mistakes. Additionally, showing your work can earn you partial credit even if your final answer is incorrect.

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