Explanation:
It is given that,
Mass of the truck, m = 2000 kg
Initial velocity of the truck, u = 34 km/h = 9.44 m/s
Final velocity of the truck, v = 58 km/h = 16.11 m/s
(a) Change in truck's kinetic energy, 



(b) Change in momentum of the truck, 


Hence, this is the required solution.
Answer:
b. The reflection of light from a smooth surface is called specular reflection.
c. The reflection of light from a rough surface is called diffuse reflection.
Explanation:
a. The angle of incidence is equal to the angle of reflection only when a ray of light strikes a plane mirror.
This is wrong: Based on law of reflection "The angle of incidence is equal to the angle of reflection when light strikes any plane surface" examples plane mirrors, still waters, plane tables, etc
b. The reflection of light from a smooth surface is called specular reflection.
This is correct
c. The reflection of light from a rough surface is called diffuse reflection.
This is correct
d. For diffuse reflection, the angle of incidence is greater than the angle of reflection.
This is wrong: the angle of incident is equal to angle of reflection. The only difference between this type of reflection and specular reflection, is that the normal for diffuse reflection is not parallel to each due to the rough surface in which the light incidents.
For specular reflection, the angle of incidence is less than the angle of reflection.
This is wrong: the angle of incident is equal to angle of reflection
Explanation:
Power = Work done ÷ Time
P = 28056 ÷ 45 Watt
<u>P</u><u> </u><u>=</u><u> </u><u>6</u><u>2</u><u>3</u><u>.</u><u>4</u><u>6</u><u> </u><u>Watt</u>
Alpha particles have both high mass and low velocity, but it would be the former that determines why they can't penetrate. An alpha particle is made of two protons and two neutrons, which is quite a large mass for a particle. This large mass keeps it from penetrating too deeply into anything, since it will essentially "get stuck" when it comes too near to another atom.
So the answer, I believe, is B. Alpha particles have high mass.