Answer:
Explanation:
This is the case of L-R charging circuit , for which the formula is as follows
i = i₀ ( 1 - )
Differentiating the equation on both sides
di / dt = i₀ / τ x
i is current at time t , i₀ is maximum current , τ is time constant which is equal to L / R where L is inductance and R is resistance of the circuit .
τ = L / R = 9 x 10⁻³ / 230
= 39 x 10⁻⁶ s
i₀ = 12 / 230 = 52.17 x 10⁻³
di / dt (at t is zero) = 52.17 x 10⁻³ / 39 x 10⁻⁶
= 1.33 x 10³ A / s
Time to reach 85 % of steady state or i₀
.85 =
= .15
t / τ = ln .15
t = 74 μs
Answer:
Explanation:
Given
Required
Determine the speed of B w.r.t A
The question implies that, we determine the relative velocity of B w.r.t A
Because both trains are moving towards one another, the required velocity is a both trains:
This is shown below:
Answer:
The correct reaction force in response to Heidi's action force is:
c. The friction is equal to 660 N since the beam is not accelerating.
Explanation:
Heidi's action force does not affect the beam. Since friction resists the sliding or rolling of one solid object over another, there is no friction acting on the beam, in this respect. The reaction force is what makes the dog to move because it acts on it. According to Newton's Third Law of Motion, forces always come in action-reaction pairs. This Third Law states that for every action force, there is an equal and opposite reaction force. This means that the dog exerts some force on Heidi, as he pulls it "forward with a force of 9.55 N."
Trees. Every time the wind blows there is a wave of motion which is movement