Answer:
60 rad/s
Explanation:
∑τ = Iα
Fr = Iα
For a solid disc, I = ½ mr².
Fr = ½ mr² α
α = 2F / (mr)
α = 2 (20 N) / (0.25 kg × 0.30 m)
α = 533.33 rad/s²
The arc length is 1 m, so the angle is:
s = rθ
1 m = 0.30 m θ
θ = 3.33 rad
Use constant acceleration equation to find ω.
ω² = ω₀² + 2αΔθ
ω² = (0 rad/s)² + 2 (533.33 rad/s²) (3.33 rad)
ω = 59.6 rad/s
Rounding to one significant figure, the angular velocity is 60 rad/s.
It should be the B
Low frequency and long wavelength
Answer:
the wavelength is 9.8 meters
Explanation:
We can use the relationship:
Velocity = wavelenght*frequency.
Initially we have:
wavelenght = 4.9m
velocity = 9.8m/s
then:
9.8m/s = 4.9m*f
f = 9.8m/s/4.9m = 2*1/s
now, if the velocity is doubled and the frequency remains the same, we have:
2*9.8m/s = wavelenght*2*1/s
wavelenght = (2*9.8m/s)*(1/2)s = 9.8 m
They would fall with the same acceleration
