X hits on this document

175 views

0 shares

1 / 16

Practice Test 3

1. Consider the following three arrangements of battery, bulb and wire(s). Circle the arrangement(s) where you predict the bulb would glow. In the space below the pictures, explain why you think so. If you do not think any of the bulbs would glow, explain why not.

A. B.

C.

The tip of the bulb touches the positive end of the battery, on the knob. A wire touches the negative end of the battery and the flat part of the positive end of the battery.

The screwy side of the bulb touches the negative end of the battery. A wire touches the bottom tip of the bulb and the flat part of the positive end of the battery.

The bottom tip of the bulb touches the negative end of the battery. There are two wires. One wire touches the screwy side of the bulb and the negative end of the battery. The other wire touches the negative end of the battery and the knob on the positive end of the battery.

In order for the bulb to light both its metal tip and the metal side need to be connected, one to each end of the battery. When this is done a complete circuit is established from one end of the battery, through the bulb, and then to the other end of the battery. Then electric current can flow round the circuit, through the bulb, thus making it light.

A WILL NOT LIGHT. The tip of the bulb is connected to the + end of the battery, but the side of bulb is not connected to anything. Electric current cannot flow through the bulb.

B

WILL LIGHT. The metal tip of the bulb is connected to the + end of the battery by the wire (Note: the wire does not need to touch the ‘knob’ on the end.) and the side

 Document views 175 Page views 223 Page last viewed Sat Jan 21 00:33:24 UTC 2017 Pages 16 Paragraphs 355 Words 3469