Answer:
The acceleration would be positive, pointing to the right.
Explanation:
The acceleration tells us how velocity changes every second. If the train stops, this means its velocity must go from a non-zero value to zero.
To reduce velocity, acceleration must point to the opposite direction. Since velocity is negative, acceleration must be positive.
Sound energy cannot travel through a vacuum.
Explanation:
Waves are periodic disturbance of the space, which travel carrying energy but not matter.
There are two types of waves:
- Mechanical waves: mechanical waves propagate through the vibrations of the particles in a medium. Examples of mechanical waves are sound waves.
- Electromagnetic waves: these waves consist of periodic oscillations of electric and magnetic fields, perpendicular to each other. These waves do not need a medium to propagate, so they can also travel in a vacuum.
In this problem, we are analyzing sound energy, which is the energy carried by sound waves. Sound waves are mechanical waves, so they need a medium to propagate: therefore, they cannot travel through a vacuum, since there is no medium.
So, sound energy cannot travel through a vacuum.
Learn more about waves:
brainly.com/question/5354733
brainly.com/question/9077368
#LearnwithBrainly
Answer:
These acts of attraction and repulsion are called “magnetism”, and the magnetic space around a magnet is called the “magnetic field”
Explanation:
Answer:
-4×-2y=14 (1)
-10×+7y=-25 (2)
multiplying eq 1 by 7 and eq 2 by 2 and add eq. 1 and 2
-28×-14y=98
-20×+14y=-50
___________
-28×=48
×=48/-28
×=-12/7
now
-4×-2y=14
-4*-12/7-2y=14
48/7-2y=14
-2y=14-48/7
-2y=(98-48)/7
-2y=50/7
y=-50/14
y=-25/7
