Answer:
the answer is C
Explanation:
C) friction - mechanical - electrical
Answer:
E = 10t^2e^-10t Joules
Explanation:
Given that the current through a 0.2-H inductor is i(t) = 10te–5t A.
The energy E stored in the inductor can be expressed as
E = 1/2Ll^2
Substitutes the inductor L and the current I into the formula
E = 1/2 × 0.2 × ( 10te^-5t )^2
E = 0.1 × 100t^2e^-10t
E = 10t^2e^-10t Joules
Therefore, the energy stored in the inductor is 10t^2e^-10t Joules
The net force acting on the object perpendicular to the table is
∑ F[perp] = F[normal] - mg = 0
where mg is the weight of the object. Then
F[normal] = mg = (15 kg) (9.8 m/s²) = 147 N
The maximum magnitude of static friction is then
0.40 F[normal] = 58.8 N
which means the applied 40 N force is not enough to make the object start to move. So the object has zero acceleration and does not move.
Answer:
F = π/4 ρ d² v²
Explanation:
Force is mass times acceleration:
F = ma
Acceleration is change in velocity over change in time:
F = m Δv / Δt
Since there's no rebound, Δv = v.
F = m v / Δt
Mass is density times volume:
F = ρ V v / Δt
Volume per time is flow rate:
F = ρ Q v
Flow rate is velocity times cross sectional area:
F = ρ (v A) v
F = ρ A v²
Area of a circle is pi times radius squared, or pi/4 times diameter squared:
F = ρ (π/4 d²) v²
F = π/4 ρ d² v²