Amotor produces a torque of 22 nm. it is used to accelerate a wheel of radius 10cm and moment of inertia 2 kg. m2 which is initially at rest. calculate

a)

the number of revolutions made by the wheel in the first 5s

b)

the angular velocity after 5s

c)

the acceleration of a point on the rim of the wheel after 5s

Answer

given,

torque produced, τ = 22 N.m

Radius of the wheel. r = 10 cm

Moment of inertial = 2 kg.m²

initial angular speed = 0 rad/s

time, t = 5 s

a) we know,

   τ = I α

   22 = 2 x α

    α = 11 rad/s²

  using equation of rotation motion

  θ = 137.5 rad

  θ = 137.5/2π  =  22 revolution.

b) angular velocity of the motor

c) acceleration of a point on the rim of the wheel

  radial acceleration

tangential acceleration of the point on the rim

now, acceleration of the point

laticia draws the diagram below to show earth’s magnetic field.

answer

the arrows to the right of earth should point up.