Answer:
Car B has a mass of 800 kg.
General Formulas and Concepts:
<u>Momentum</u>
Law of Conservation of Momentum: 
Explanation:
<u>Step 1: Define</u>
<em>Identify variables</em>
[Given] m₁ = 1200 kg
[Given] v₁i = 10 m/s
[Solve] m₂
[Given] v₂i = 0 m/s
[Given] vf = 6 m/s
<u>Step 2: Solve for m₂</u>
- Substitute in variables [Law of Conservation of Momentum]: (1200 kg)(10 m/s) + m₂(0 m/s) = (1200 kg + m₂)(6 m/s)
- Multiply: 12000 kg · m/s = (1200 kg + m₂)(6 m/s)
- Isolate m₂ term: 2000 kg = 1200 kg + m₂
- Isolate m₂: 800 kg = m₂
Use the formula n = c / v, where c is the speed of light and v is the speed of light in the environment, that is, use the speed in brackets and the correct answer will be the one that will be the smallest result
stable equilibrium, if displaced from equilibrium, it experiences a net force or torque in a direction opposite to the direction of the displacement.
unstable equilibrium, if displaced it experiences a net force or torque in the same direction as the displacement from equilibrium. A system in unstable equilibrium accelerates away from its equilibrium position if displaced even slightly.
neutral equilibrium, is when an equilibrium is independent of displacements from its original position.
Have a good day, hope this helps
Answer:
Velocity, v = 0.239 m/s
Explanation:
Given that,
The distance between two consecutive nodes of a standing wave is 20.9 cm = 0.209 m
The hand generating the pulses moves up and down through a complete cycle 2.57 times every 4.47 s.
For a standing wave, the distance between two consecutive nodes is equal to half of the wavelength.

Frequency is number of cycles per unit time.

Now we can find the velocity of the wave.
Velocity = frequency × wavelength
v = 0.574 × 0.418
v = 0.239 m/s
So, the velocity of the wave is 0.239 m/s.