Answer:
1.3 rev/s
Explanation:
= Moment of inertia when arms and one leg of the skater is out = 3.5 kgm²
= Moment of inertia when arms and legs of the skater are in = 0.80 kgm²
= Angular speed of skater when arms and legs of the skater are in = 5.5 rev/s
= Angular speed of skater when arms and legs of the skater are out = ?
Using conservation of angular momentum
=
(0.80) (5.5) = (3.5)
= 1.3 rev/s
Answer:modeled as an electromagnetic wave. In this model, a changing electric field creates a changing magnetic field.
Explanation:
Answer:
The electric force between A and B will increase.
Explanation:
Answer:
From question (a) and (b) the pendulum motion is perpendicular to the force so the normal force will do no work and the tension in the string of the pendulum will not work

And
so

c
An example will be a where a stone is attached to the end of a string and is made to move in a circular motion while keeping the other end of the string in a fixed position
d
A dog walking along a surface which has friction, here the frictional force would acting in the direction of the motion and this would do positive work
Explanation: