Answer:
B. Ball Y will travel at a speed less than 5 m/s in the opposite direction of travel as before the collision.
Explanation:
Impulse created by ball Y on ball X = 40 x 1/6 Ns
Ball X will also create impulse 40 / 6 on ball Y .
impulse = change in momentum .
impulse in Y = change in momentum in Y .
Initial momentum of Y = .5 x 5 = 2.5
Let final velocity of Y after collision be v in opposite direction .
change in momentum of Y = v - (-2.5 )
so,
v + 2.5 = 40 / 6 = 6.67
v = 4.17 m / s .
Option B is correct .
B. Ball Y will travel at a speed less than 5 m/s in the opposite direction of travel as before the collision.
Answer: C. Charge and distance
Answer:
New Resistance = 0.5556 ohm
Explanation:
Resistance = resistivity * length /area
Here since resistivity and length are constant, we only need to see how the resistance increases or decreases with change in area.
New Area = pi * (3*D)^2 / 4
Old Area = pi * D^2 / 4
The ratio of new area / old area is :

Since area increases 9 times, and it is inversely proportional to resistance:
Resistance decreases by 9 times.
So, old resistance = Voltage / Current = 10 / 2 = 5 ohm
New Resistance = 5 / 9 = 0.5556 ohm (decreases by 9 times)
First, figure out what the angular speed of the merry-go-around is.
v ϖ = Using the formula for linear speed Since the angular speed is constant, there is no angular acceleration. Tangential acceleration is t a Radial acceleration is r a Thus the total acceleration is a = rω =1.2m×1.6rad / s =1.9m/ s = rα =1.2m×0rad / s2 = 0m/ s2 =rϖ2 =1.2m×(1.6rad / s)2 =3.1m/ s2 2 2 t r = a +a = 0+(3.1)2 =3.1m/ s2 1 4.0 rev