Common health issues that can be positively affected, prevented or controlled by exercise.
Answer:
True
Explanation:
the horse pull on the wagon but friction and the wight + gravity make the wagon pull on the horse ( newton's 2ed law)
Well, that's a nice, concise description, but it applies to a
generator, not a motor. A motor does exactly the opposite.
It uses an electric current to produce motion in a magnetic field.
Sadly, the statement is false.
Answer:
v = 2 v₁ v₂ / (v₁ + v₂)
Explanation:
The body travels the first half of the distance with velocity v₁. The time it takes is:
t₁ = (d/2) / v₁
t₁ = d / (2v₁)
Similarly, the body travels the second half with velocity v₂, so the time is:
t₂ = (d/2) / v₂
t₂ = d / (2v₂)
The average velocity is the total displacement over total time:
v = d / t
v = d / (t₁ + t₂)
v = d / (d / (2v₁) + d / (2v₂))
v = d / (d/2 (1/v₁ + 1/v₂))
v = 2 / (1/v₁ + 1/v₂)
v = 2 / ((v₁ + v₂) / (v₁ v₂))
v = 2 v₁ v₂ / (v₁ + v₂)
