Answer:
Speed = 575 m/s
Mechanical energy is conserved in electrostatic, magnetic and gravitational forces.
Explanation:
Given :
Potential difference, U = 
Mass of the alpha particle, 
Charge of the alpha particle is, 
So the potential difference for the alpha particle when it is accelerated through the potential difference is
And the kinetic energy gained by the alpha particle is
From the law of conservation of energy, we get
The mechanical energy is conserved in the presence of the following conservative forces :
-- electrostatic forces
-- magnetic forces
-- gravitational forces
Answer:31.3W
Explanation: JUST A FORMULA
P = V*V/R = 120*120/460 = 31.3W
Option B is correct. If an incident light ray hits a flat, smooth object at 28°. It will reflect off at an angle of 28°.
<h3>What is the law of reflection?</h3>
The law of reflection specifies that upon reflection from a downy surface, the slope of the reflected ray is similar to the slope of the incident ray.
The reflected ray is consistently in the plane determined by the incident ray and perpendicular to the surface at the point of reference of the incident ray.
When the light rays descend on the smooth surface, the angle of reflection is similar to the angle of incidence, also the incident ray, the reflected ray, and the normal to the surface all lie in a similar plane.
If an incident light ray hits a flat, smooth object at 28 degrees, it will reflect off at an angle of 28°.
Hence, option B is correct
To learn more about the law of reflection, refer to the link;
brainly.com/question/12029226
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