You must observe the object twice.
-- Look at it the first time, and make a mark where it is.
-- After some time has passed, look at the object again, and
make another mark at the place where it is.
-- At your convenience, take out your ruler, and measure the
distance between the two marks.
What you'll have is the object's "displacement" during that period
of time ... the distance between the start-point and end-point.
Technically, you won't know the actual distance it has traveled
during that time, because you don't know the route it took.
Answer:
KE = 2.535 x 10⁷ Joules
Explanation:
given,
angular speed of the fly wheel = 940 rad/s
mass of the cylinder = 630 Kg
radius = 1.35 m
KE of flywheel = ?
moment of inertia of the cylinder

=
= 574 kg m²
kinetic energy of the fly wheel

KE = 2.535 x 10⁷ Joules
the kinetic energy of the flywheel is equal to KE = 2.535 x 10⁷ Joules
The other 4 kg of mass may have departed the scene
of the fire, in the form of gases and smoke particles.
Answer:
0.0061 J
Explanation:
Parameters given:
Number of turns, N = 111
Radius of turn, r = 2.11 cm = 0.0211 m
Resistance, R = 14.1 ohms
Time taken, t = 0.125 s
Initial magnetic field, Bin = 0.669 T
Final magnetic field, Bfin = 0 T
The energy dissipated in the resistor is given as:
E = P * t
Where P = Power dissipated in the resistor
Power, P, is given as:
P = V² / R
Hence, energy will be:
E = (V² * t) / R
To find the induced voltage (EMF), V:
EMF = [-(Bfin - Bin) * N * A] / t
A is Area of coil
EMF = [-(0 - 0.669) * 111 * pi * 0.0211²] / 0.125
EMF = 0.83 V
Hence, the energy dissipated will be:
E = (0.83² * 0.125) / 14.1
E = 0.0061 J