Answer:
sun is the main source while the other object reflect light on the sun
Explanation:
nasa libro yans
Because although they cannot see it, they can see it's influence on objects that can be seen, and it's effects.
Dark matter may explain <span>unexpected orbital velocities of stars in galaxies.</span>
Answer:
a) τ = 0.672 N m
, b) θ = 150 rad
, c) W = 100.8 J
Explanation:
a) for this part let's start by finding angular acceleration, when the angular velocity stops it is zero (w = 0)
w = w₀ + α t
α = -w₀ / t
α = 120 / 2.5
α = 48 rad / s²
The moment of inertia of a cylinder is
I = ½ M R²
Let's calculate the torque
τ = I α
τ = ½ M R² α
τ = ½ 2.8 0.1² 48
τ = 0.672 N m
b) we look for the angle by kinematics
θ = w₀ t + ½ α t2
θ = ½ α t²
θ = ½ 48 2.5²
θ = 150 rad
c) work in angular movement
W = τ θ
W = 0.672 150
W = 100.8 J
