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  <resource>
  <id>7601</id>
  <path>/www/nrich/html/content/id/7601/</path>
  <resourceTypeID>1</resourceTypeID>
  <last_published>0000-00-00T00:00:00</last_published>
  <indexXML>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
&lt;mdoxml version=&quot;1.0&quot;&gt;&lt;br&gt;&lt;/br&gt;
&lt;ul id=&quot;stemLinks&quot;&gt;
&lt;li&gt;&lt;a href=&quot;http://nrich.maths.org/7602&quot;&gt;Warm-up&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;http://nrich.maths.org/7636&quot;&gt;Try this next&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;http://nrich.maths.org/7603&quot;&gt;Think higher&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;http://plus.maths.org/content/os/issue36/features/nishiyama/index&quot;&gt;Read: mathematics&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;http://nrich.maths.org/7609&quot;&gt;Read: science&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;http://motivate.maths.org/conferences/conference.php?conf_id=121&quot;&gt;Explore further&lt;/a&gt;&lt;/li&gt;
&lt;/ul&gt;
&lt;div&gt; &lt;/div&gt;
&lt;p&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in; text-align: center;&quot;&gt;&lt;b&gt;&lt;u&gt;Simple series circuits&lt;/u&gt;&lt;/b&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;Match each symbol to the correct component:&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;cell.jpeg&quot; style=&quot;width: 181px; height: 137px; float: right;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;variable%20resistor.jpeg&quot; style=&quot;width: 181px; height: 137px; float: left;&quot;&gt;&lt;/mdo:image&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;battery.jpeg&quot; style=&quot;width: 222px; height: 137px; float: left;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;
&lt;p&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;inductor.jpeg&quot; style=&quot;width: 181px; height: 97px; float: right;&quot;&gt;&lt;/mdo:image&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;capacitor.jpeg&quot; style=&quot;width: 168px; height: 149px; float: left;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;voltmeter.jpeg&quot; style=&quot;width: 181px; height: 137px; float: left;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;bulb.jpeg&quot; style=&quot;width: 181px; height: 137px; float: right;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;resistor.jpeg&quot; style=&quot;width: 232px; height: 86px; float: right;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;ampmeter.jpeg&quot; style=&quot;width: 181px; height: 137px;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;Resistor, Cell, Ampmeter, Battery, Voltmeter, Variable resistor, Bulb, Capacitor, Inductor.&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;circuit%201.jpeg&quot; style=&quot;width: 305px; height: 283px; float: right;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;For the following circuit, find&lt;/p&gt;
&lt;ol type=&quot;i&quot;&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;the current supplied by the electric cell&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;the voltage through the resistor&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;the voltage through the bulb&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;the power used by the bulb&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;the total power supplied by the cell&lt;/p&gt;
&lt;/li&gt;
&lt;/ol&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;&lt;/mdoxml&gt;</indexXML>
  <solutionXML/>
  <noteXML/>
  <clueXML/>
  <canonXML>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
&lt;mdoxml version=&quot;1.0&quot;&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;Fast solutions:&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;            Variable resistor                     
Ammeter                                     Voltmeter&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;variable%20resistor.jpeg&quot; style=&quot;width: 181px; height: 137px; float: left;&quot;&gt;&lt;/mdo:image&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;ampmeter.jpeg&quot; style=&quot;width: 181px; height: 137px;&quot;&gt;&lt;/mdo:image&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;voltmeter.jpeg&quot; style=&quot;width: 181px; height: 137px;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;                   
Battery                                                  
Resistor                                              Bulb&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;battery.jpeg&quot; style=&quot;width: 222px; height: 137px;&quot;&gt;&lt;/mdo:image&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;resistor.jpeg&quot; style=&quot;width: 218px; height: 68px;&quot;&gt;&lt;/mdo:image&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;bulb.jpeg&quot; style=&quot;width: 181px; height: 137px;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;                 Inductor                                
Cell                              Capacitor&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;inductor.jpeg&quot; style=&quot;width: 181px; height: 97px;&quot;&gt;&lt;/mdo:image&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;cell.jpeg&quot; style=&quot;width: 181px; height: 137px;&quot;&gt;&lt;/mdo:image&gt;&lt;mdo:image alt=&quot;&quot; src=&quot;capacitor.jpeg&quot; style=&quot;width: 168px; height: 149px;&quot;&gt;&lt;/mdo:image&gt;&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt; &lt;/p&gt;
&lt;ol type=&quot;i&quot;&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;1/3 A&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;1V&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;2V&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;2/3 W&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;1W&lt;/p&gt;
&lt;/li&gt;
&lt;/ol&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt; &lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in&quot;&gt;Detailed solutions:&lt;/p&gt;
&lt;ol type=&quot;i&quot;&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;the total resistance of the circuit is&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;$3\Omega + 6\Omega = 9\Omega$ because this is a series circuit and therefore resistances add up&lt;/p&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;V=IR so 3 = I x 9 so I = 3/9 = 1/3 A&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;The voltage across the resistor:V=IR so V=1/3 x 3 = 1V because the current is the same through the bulb and the resistor&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;the voltage through the bulb is:&lt;br&gt;&lt;/br&gt;
V=IR so V=1/3 x 6 = 2V or because the total voltage across the whole circuit is 3V and the resistor is taking up 1V, we know that the bulb is taking 3V - 1V = 2V.&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;The power used by the bulb:&lt;br&gt;&lt;/br&gt;
Power=IV so P=1/3 x 2 = 2/3 Watts&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p style=&quot;margin-bottom: 0in;&quot;&gt;The total power supplied by the cell:&lt;br&gt;&lt;/br&gt;
P = IV so P = 1/3 x 3 = 1 Watt&lt;br&gt;&lt;/br&gt;
This means that the resistor must be dissipating 1 - 2/3 = 1/3 Watts&lt;/p&gt;
&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt; &lt;/p&gt;

&lt;/mdoxml&gt;</canonXML>
  <end_user_role>2</end_user_role>
  <difficulty>3</difficulty>
  <keystage1>0</keystage1>
  <keystage2>0</keystage2>
  <keystage3>1</keystage3>
  <keystage4>0</keystage4>
  <keystage4plus>0</keystage4plus>
  <title>Electrical circuits I</title>
  <description>Simple electronic circuit problem to revise series circuits.</description>
  <spec_group>Applications
    <specifier>STEM - physical world</specifier>
  </spec_group>
  <spec_group>Admin
    <specifier>STEM - needs something doing</specifier>
  </spec_group>
</resource>