Answer: 3
Explanation:
Given
One cloud is traveling at rate of 
combined velocity of the two is 
Suppose the masses of the clouds be 
Conserving momentum

Answer:
A) The crossbeam is moving relative to the observer on the platform so the height appears contracted.
Explanation:
The observer on the train and the beam are in the same reference frame. That means observer on the train will measure the proper length of the beam not the contracted length . the observer is outside and the plank is in the moving system,it will appear to be moving.
Answer:
(c) no different than on a low-pressure day.
Explanation:
The force acting on the ship when it floats in water is the buoyant force. According to the Archimedes' principle: The magnitude of buoyant force acting on the body of the object is equal to the volume displaced by the object.
Thus, Buoyant forces are a volume phenomenon and is determined by the volume of the fluid displaced.
<u>Whether it is a high pressure day or a low pressure day, the level of the floating ship is unaffected because the increased or decreased pressure at the all the points of the water and the ship and there will be no change in the volume of the water displaced by the ship.</u>
The speed of the ball moving is

what is momentum?
The momentum p of a classical object of mass m and velocity v is given by pclassical =mv.
For photons with wavelength λ,this equation does not hold.Instead, the momentum of the Photon is given by p Photon = h/λ
where,h is the planck's constant.
The momentum of the red Photon is
given:




since,the Photon and the ping-pong ball have the same momentum,we have



Therefore, if the red photon and the ping-pong ball have the same momentum, the ping-pong ball must have a speed of approximately

learn more about momentum of photon from here: brainly.com/question/28197406
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If the motorcycle can go from 0 to 50mph in 3 seconds the person is describing the motorcycle's acceleration.