Answer:
At the bottom when they hit the ground.
Answer:

Explanation:
The centripetal acceleration of a point moving by circular motion is given by:

where
is the angular velocity
r is the distance from the axis of rotation
The point on the wheel makes 5.0 revolutions per second, so the frequency is

and the angular velocity is

While the distance of the point from the axis of rotation is

Substituting, we find the acceleration:

Answer:
12 kg
Explanation:
Momentum before collision = momentum after collision
m₁ u₁ + m₂ u₂ = m₁ v₁ + m₂ v₂
After the collision, they have the same velocity, so v₁ = v₂ = v:
m₁ u₁ + m₂ u₂ = m₁ v + m₂ v
m₁ u₁ + m₂ u₂ = (m₁ + m₂) v
We know that m₁ = 6 kg, u₂ = 0 m/s, and v = u₁ / 3.
(6 kg) u₁ + m₂ (0 m/s) = (6 kg + m₂) (u₁ / 3)
(6 kg) u₁ = (6 kg + m₂) (u₁ / 3)
6 kg = (6 kg + m₂) (1/3)
18 kg = 6 kg + m₂
m₂ = 12 kg
The answer is 30 ... same as the Atomic number.