<span>The number of the group identifies the column of the standard periodic table in which the element appears.</span>
Group 1 contains the alkali metals ( lithium<span> (</span>Li<span>), </span>sodium<span> (</span>Na<span>), </span>potassium<span> (</span>K<span>), </span>rubidium<span> (</span>Rb<span>), </span>caesium<span> (</span>Cs<span>), and </span>francium(Fr).)<span>
Group 2 contains the alkaline earth metals (</span> beryllium<span> (</span>Be),magnesium<span> (</span>Mg<span>), </span>calcium<span> (</span>Ca<span>), </span>strontium<span> (</span>Sr<span>), </span>barium<span> (</span>Ba<span>) and </span>radium<span> (</span>Ra<span>) )
Group 3: </span><span> Scandium (Sc) and yttrium (Y) </span>
This problem is to let you practice using Newton's second law of motion:
Force = (mass) x (acceleration)
-- The airplane's mass when it takes off (before it burns any of its load of fuel) is 320,000 kg.
-- The force available is (240,000 N/per engine) x (4 engines) = 960,000 N.
-- Now you know ' F ' and ' mass '. Use Newton's second law of motion to calculate the plane's acceleration.
-I believe the star gives off energy-, With<span> most </span>stars<span>, like our sun, hydrogen </span>is<span> being converted into Helium, a process which gives </span>off<span> energy that heats the </span>star<span>.</span>
Answer:
8.97 Watt
Explanation:
Resistance, R = 20 ohm
Inductance, L = 10 mH
V(t) = 20 Cos (1000 t + 45°)
Compare with the standard equation
V(t) = Vo Cos(ωt + Ф)
Ф = 45°
ω = 1000 rad/s
Vo = 20 V
Inductive reactance, XL = ωL = 1000 x 0.01 = 10 ohm
impedance is Z.
Z = 22.36 ohm
Apparent power is given by
P = Vrms x Irms
P = 14.144 x 0.634
P = 8.97 Watt
