Answer:
The correct answer is a
Explanation:
At projectile launch speeds are
X axis vₓ = v₀ = cte
Y axis = v_{oy} –gt
The moment is defined as
p = mv
For the x axis
pₓ = mvₓ = m v₀ₓ
As the speed is constant the moment is constant
For the y axis
p_{y} = m v_{y} = m (v_{oy} –gt) = m v_{oy} - m (gt)
Speed changes over time, so the moment also changes over time
Let's examine the answer
i True
ii False. The moment changes with time
The correct answer is a
Answer:
F_A = 8 F_B
Explanation:
The force exerted by the planet on each moon is given by the law of universal gravitation
F =
where M is the mass of the planet, m the mass of the moon and r the distance between its centers
let's apply this equation to our case
Moon A
the distance between the planet and the moon A is r and the mass of the moon is 2m
F_A = G \frac{2m M}{r^{2} }
Moon B
F_B = G \frac{m M}{(2r)^{2} }
F_B = G \frac{m M}{4 r^{2} }
the relationship between these forces is
F_B / F_A = = 1/8
F_A = 8 F_B
Answer:
Yes, if the two carts are moving into opposite directions
Explanation:
The total momentum of the system of two carts is given by:
where
m1, m2 are the masses of the two carts
v1, v2 are the velocities of the two carts
Let's remind that v (the velocity) is a vector, so its sign depends on the direction in which the cart is moving.
We want to know if it is possible that the total momentum of the system can be zero, so it must be:
From this equation, we see that this condition can only occur if v1 and v2 have opposite signs. Opposite signs mean opposite directions: therefore, the total momentum can be zero if the two carts are moving into opposite directions.