No. I do not agree with Stefan. Quite the contrary. I disagree
with his description of "<span>angle of incidence" as the angle between
the surface of the mirror and the incoming ray.
The correct description of "angle of incidence" is </span><span>the angle between
the NORMAL TO the surface of the mirror and the incoming ray.
Thus, the true angle of incidence is the complement of the angle that
Stefan calculates or measures.</span>
It takes work to push charge through a change of potential.
There's no change of potential along an equipotential path,
so that path doesn't require any work.
Answer:
v’ =(
) v
we see that the greater the difference, the more the sled slows down.
friction force
Explanation:
When the man pushes the sled he does work and the sled acquires a speed and as long as it is supplied with an energy equal to the work of the chipping force with the snow, the speed is maintained.
When he jumps on the sled, a collision occurs and the initial moment
p₀ = mv
is increased by the increase in mass
m_f= (m + M_{man} ) v '
In this case there is no longer any external force applied and the only external force is friction, which causes the sled to stop, even when it is small, but the significant reduction in speed is due to the increase in masses.
p₀ = p_f
mv = (m + M_{man}) v '
v ’=
v
v’ =(
) v
Therefore, we see that the greater the difference, the more the sled slows down.
The only forces that act on the sled with the man are the friction that is responsible for the decrease in speed and weight with the normal