Answer:
Alpha = ω^2 R where R is radius of blade
g = w^2 r where r is distance from center
ω^2 R = 11.5 ω^2 r
R / r = 11.5 / 9.8 = 1.17
Or r = .852 R
Since the angular acceleration depends on both R and ω it seems that one can only get r as it depends on R
Answer:
Vy = 26 m/s sin 30 = 13 m/s vertical speed
t = Vy / a = 13 m/s / 9.80 m/s^2 = 1.33 sec time to reach Vy = 0
H = Vy t + 1/2 g t^2
H = 13 m/s * 1.33 sec - 1.33^2 * 9.8 / 2 m = 8.62 m
Answer:
ω' = 2.5 rad/s
Explanation:
mass of cockroach, m = 4 kg
mass of disk, M = 6 kg
Radius of disc= R
initial angular velocity, ω = 2 rad/s
Let the final angular velocity is ω'
As no external torque is applied, so the angular momentum is constant.
Angular momentum = Moment of inertia x angular velocity
I ω = I' ω'


ω' = 2.5 rad/s
To find average speed, we divide the distance of travel (in this case, 400 metres) by the time she took, 32 seconds. Therefore: 12.5 seconds is her average speed.