Answer
given,
cooling fan revolution = 850 rev/min
fan turns before revolution = 1500 revolutions


θ = 1500 revolution
θ = 1500 x 2 x π
θ = 9424.78 rad
a) using equation of rotation
ω² = ω₀² + 2 α θ
ω = 0 because body comes to rest
0 = 89² + 2 x α x 9424.78
α = -0.42 rad/s²
b) time take for the fan to stop
ω = ω₀ + α t
0 = 89 - 0.42 t

t = 211.9 s
Answer:
Angle of incline is 20.2978°
Explanation:
Given that;
Gravitational acceleration on a planet a = 3.4 m/s²
Gravitational acceleration on Earth g = 9.8 m/s²
Angle of incline = ∅
Mass of the stone = m
Force on the stone along the incline will be;
F = mgSin∅
F = ma
The stone has the same acceleration as that of the gravitational acceleration on the planet.
so
ma = mgSin∅
a = gSin∅
Sin∅ = a / g
we substitute
Sin∅ = (3.4 m/s²) / (9.8 m/s²)
Sin∅ = 0.3469
∅ = Sin⁻¹( 0.3469 )
∅ = 20.2978°
Therefore, Angle of incline is 20.2978°
Answer:
p = 1.16 10⁻¹⁴ C m and ΔU = 2.7 10 -11 J
Explanation:
The dipole moment of a dipole is the product of charges by distance
p = 2 a q
With 2a the distance between the charges and the magnitude of the charges
p = 1.7 10⁻⁹ 6.8 10⁻⁶
p = 1.16 10⁻¹⁴ C m
The potential energie dipole is described by the expression
U = - p E cos θ
Where θ is the angle between the dipole and the electric field, the zero value of the potential energy is located for when the dipole is perpendicular to the electric field line
Orientation parallel to the field
θ = 0º
U = 1.16 10⁻¹⁴ 1160 cos 0
U1 = 1.35 10⁻¹¹ J
Antiparallel orientation
θ = 180º
cos 180 = -1
U2 = -1.35 10⁻¹¹ J
The difference in energy between these two configurations is the subtraction of the energies
ΔU = | U1 -U2 |
ΔU = 1.35 10-11 - (-1.35 10-11)
ΔU = 2.7 10 -11 J