Answer:
three balls have the same speed
Explanation:
In a parabolic motion we have that
but the time just before the balls hit the ground is
Hence we have
ball A
ball B
ball C
Hence, all three balls have the same speed just before hit the groug
vA=vB=vC
I hope this is useful for you
regards
The answer is A John Roebling.
Answer:
b
Explanation:
because I dont know I guess I learned it in school
The answer is 4.0 kg since the flywheel comes to rest the
kinetic energy of the wheel in motion is spent doing the work. Using the
formula KE = (1/2) I w².
Given the following:
I = the moment of inertia about the
axis passing through the center of the wheel; w = angular velocity ; for the
solid disk as I = mr² / 2 so KE = (1/4) mr²w². Now initially, the wheel is spinning
at 500 rpm so w = 500 * (2*pi / 60) rad / sec = 52.36 rad / sec.
The radius = 1.2 m and KE = 3900 J
3900 J = (1/4) m (1.2)² (52.36)²
m = 3900 J / (0.25) (1.2)² (52.36)²
m = 3.95151 ≈ 4.00 kg