Answer:
(a) Angular acceleration is 1.112 rad/s².
(b) Average angular velocity is 2.78 rad/s .
Explanation:
The equation of motion in Rotational kinematics is:
θ = θ₀ + 0.5αt²
Here θ is angular displacement at time t, θ₀ is angular displacement at time t=0, t is time and α is constant angular acceleration.
(a) According to the problem, θ is 13.9 rad, θ₀ is zero as it is at rest and t is 5 s. Put these values in the above equation:
13.9 = 0 + 0.5α(5)²
α = 1.112 rad/s²
(b) The equation of average angular velocity is:
ω = Δθ/Δt
ω = 
ω = 2.78 rad/s
<span>It is measured in calories </span>
Answer:
When a ball thrown upward reaches its highest point, its velocity is? is still -9.8 m/s2. The acceleration due to gravity is always -9.8 m/s/s, regardless of the ball's velocity.
<h2>
Answer:20.97g N,32.63g N</h2>
Explanation:
We consider the forces at the knot.
The vertical forces are
is the vertical component of tension 
at the knot.
is the weight of the mass 
acting downwards.
The horizontal forces are
is the tension in the rope acting left.
is the horizontal component of tension acting towards right.
Since the knot has no mass,it is always in equilibrium.
So,the sum of forces acting on it will be zero.
Balancing vertical forces gives,
=
Balancing horizontal forces gives,
Friction, gravity, normal force, and the brakes constitute an applied force.
