P 7 Revision

Complete these sentences on The Motor Effect...

The MOTOR EFFECT is when a c______ carrying device is put between m_______ p___(s). The magnetic field around the w___ interacts with the magnetic field it is p_____ in. This causes the magnetic and the c________ to exert a f____ on one another.

(a)  

Complete these questions on the MOTOR EFFECT...

To experience the full force the wire has to be at __ degrees to the m_______ f____.

The force always acts at r____ a____(s) to the magnetic field of the magnets and to the direction of the c______ in the wire.

If the wire runs parallel to the magnetic field , it wont experience any f____ at all.

The magnetic strength of the force i_______(s) with the strength of the m_______ f____.

Force also increases with the amount of c______ passing through the c________.

(a)  

Complete the equation for Force...

FORCE = M_______ F___ D______ X C______ X L_____

(a)  

What do magnets produce?

(a)  

All magnets have two poles. What are they?

• North

• South

• East

• West

Complete these sentences on MAGNETS...

Magnetic Fields are shown by magnetic field l___(s). The c_____ the lines are the s_______ the magnetic field. The lines always go from n____ to s____.

Magnetic field is strongest at the p___(s) of a magnet.

(a)  

Complete these sentences about MAGNETS...

Compasses show the d________ of a magnetic field. To draw a magnetic field you move a compass around a m_____ and trace the n_____(s) position to build up a picture of the magnetic field.

(a)  

Complete these sentences on TRANSFORMERS...

Transformers change the size of the p________ d_________of an AC

Two c___(s) joined with an i___ core

Alternating __ is applied across the p______ coil, the i___core magnetises and d__________(s) quickly.

Second coil is part of a c_______ circuit.

Ratio between the number of turns of primary and secondary coil = p________ d_________ of primary and secondary coil.

(a)  

Complete these sentences on LOUDSPEAKERS...

1) AC is sent through a c___ of w___ attached to the base of a p____ c___

2) Coil surrounds one p___ of a permanent magnet and is surrounded by the other. C______ causes a force on coil.

3) Current r______(s), the force acts in the o_______ direction

4) Variations in the current make core v______. A__ around the core vibrates and creates vibrations in p_______ that cause a sound wave.

5) F________ of sound wave = F________ of AC

(a)  

Complete these sentences on MICROPHONES...

1) Sound waves hit a flexible d________ that is attached to a c___ of w___

2) This causes the coil to m___ in the m_______ f____, which generates a c______

3) Movement of the coil depends on the p________(s) of the sound wave

4) Microphones can convert the p_______ variations of a sound wave into variations in the c______ in an e_______ circuit

(a)