Answer:
Option D.
Value cannot be calculated without knowing the speed of the train
Explanation:
The speed of the beam can only be calculated accurately when the speed of the train is put into consideration. Based of the theory of relativity, the observer is on the ground, and the train is moving with the beam of light inside it. This causes a variation in the reference frames when making judgements of the speed of the beam. The speed of the beam will be more accurate if the observer is moving at the same sped of the train, or the train is stationary.
To get the correct answer, we have to subtract the speed of the train from the speed calculated.
Answer:
the rocks have the same amount of thermal energy
Answer:
V' = 0.84 m/s
Explanation:
given,
Linear speed of the ball, v = 2.85 m/s
rise of the ball, h = 0.53 m
Linear speed of the ball, v' = ?
rotation kinetic energy of the ball

I of the moment of inertia of the sphere

v = R ω
using conservation of energy


Applying conservation of energy
Initial Linear KE + Initial roational KE = Final Linear KE + Final roational KE + Potential energy



V'² = 0.7025
V' = 0.84 m/s
the linear speed of the ball at the top of ramp is equal to 0.84 m/s
A lightbulb carries more current immediately after it is turned on and the glow of the metal filament is increasing; option A.
<h3>What is current?</h3>
Current refers to the flow of electric charges typically electrons.
Current flowing through a metallic material decreases with increase in temperature of the material.
This is because the resistance of the metal increases with increase in temperature.
Therefore, for a light bulb, the current flow through it will be maximum when it is just turned on because the temperature, and hence the resistance of the filament is at its lowest.
In conclusion, current flow decreases with increase in resistance.
Learn more about current and resistance at: brainly.com/question/24858512
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