Answer:

Explanation:
Given data:
Rotating cylinder length = 9 mi
diameter of cylinder is 5.9 mi
we know that linear acceleration is given as
a = r ω^2
where ω is angular velocity
so



C.
The force of friction = coefficient of friction * normal force.
Adding the book to the boy increases the normal force and the component of the gravitational force directed down the slide. This in turn increases the force of friction as can be seen by the relationship from the above equation. For a stationary object, the force of static friction is always equal to the force applied (in this case, it is the component of the gravitational force directed down the slide). That means that so long as the boy is not moving and his mass increases, the frictional force is increasing also to balance the increased downward gravitation force directed down the slide.
At that point it is no longer trying to uncompress nor is it trying to stretch. This is the same thing as a pendulum at the bottom of its swing, no longer falling but not yet rising against gravity. Thus the kinetic energy there is the same as the potential energy when it is compressed. The energy of compression is

This gives E=0.5(37)(0.2)²=
0.74JThis is the same as the kinetic energy when it is at natural length
Answer:
Explanation:
In the calculation of distance we do not take into account the direction of movement .So only magnitude of movement is taken care of.
On the other hand , in respect of displacement , we take into account even direction of movement along with magnitude.
Distance covered by flea = 45 - 27 = 18 cm
Displacement by flea = 27 - 45 = - 18 cm
Speed = Distance covered / time
= 18 / 3 = 6 cm / s
Velocity = - 18 / 3 = - 6 cm /s.