∑F = ma = (90 kg)(1.2 m/s²) = 108 N = 100 N (1 significant digit)
Answer:
it just pulls them at the same time
Explanation:
Answer: 5.5m/s
Explanation:
vf=vi+at
vf= 4.0m/s + (0.50m/s^2)(3.0s)
The equation for electrical power is<span>P=VI</span>where V is the voltage and I is the current. This can be rearranged to solve for I in 6(a).
6(b) can be solved with Ohm's Law<span>V=IR</span>or if you'd like, from power, after substituting Ohm's law in for I<span>P=<span><span>V2</span>R</span></span>
For 7, realize that because they are in parallel, their voltages are the same.
We can find the resistance of each lamp from<span>P=<span><span>V2</span>R</span></span>Then the equivalent resistance as<span><span>1<span>R∗</span></span>=<span>1<span>R1</span></span>+<span>1<span>R2</span></span></span>Then the total power as<span><span>Pt</span>=<span><span>V2</span><span>R∗</span></span></span>However, this will reveal that (with a bit of algebra)<span><span>Pt</span>=<span>P1</span>+<span>P2</span></span>
For 8, again the resistance can be found as<span>P=<span><span>V2</span>R</span></span>The energy usage is simply<span><span>E=P⋅t</span></span>
Answer:
0.0133 A
Explanation:
The time at which B=1.33 T is given by
1.33 = 0.38*t^3
t = (1.33/0.38)^(1/3) = 1.52 s
Using Faraday's Law, we have
emf = - dΦ/dt = - A dB/dt = - A d/dt ( 0.380 t^3 )
Area A = pi * r² = 3.141 *(0.025 *0.025) = 0.00196 m²
emf = - A*(3*0.38)*t^2
thus, the emf at t=1.52 s is
emf = - 0.00196*(3*0.38)*(1.52)^2 = -0.0052 V
if the resistance is 0.390 ohms, then the current is given by
I = V/R = 0.0052/0.390 = 0.0133 A