Explanation:
<em>Law of conservation of energy states that the energy of a system is always constant. </em>
In other words, we can say that energy can neither be created nor destroyed.
Mechanical energy (E) is the sum of the potential energy (U) and the kinetic energy (K) of the freely falling body. Therefore, <em><u>E=K+U=constant.</u></em>
Answer:
a) 83.33 rad/s^2
b) 2500 rad/s
c) 6187.5 rad
Explanation:
Given data:
radius of wheel = 20.0 cm
mass of wheel = 3.0 kg
force = 25 N
a) angular acceleration
we know torque is given as



solving for angular acceleration 

b) angular velocity
duartion of force applied = 30.0 sec

= o + 83.33 *30 = 2500 rad/sec
c) angular displacement




Time = (distance) / (speed)
Distance = 3,000 km = 3,000,000 meters
Speed = 200 m/s
Time = (3,000,000 m) / (200 m/s)
Time = <em>15,000 seconds</em>
That's 4 hours 10 minutes
-- Charges with the same sign repel each other.
-- Charges with different signs attract each other.
-- This is called the "electrostatic force".
-- There's another set of forces called "magnetic forces", but
-- there's no such thing as "electromagnetic force".
3. A loudspeaker works because of the “motor effect” meaning electricity and a magnetic field cause movement.
4. A direct current will cause momentary movement in one direction only. For the speaker to produce sound you would need alternating current which makes the cone vibrate back & forth.