P5

Question 1

What is the symbol for an ammeter?

Answer 1

—–(A)—–

Question 2

What is the symbol for a voltmeter?

Answer 2

—–(V)—–

Question 3

How do you calculate resistance (in ohms)?

Answer 3

Voltage/current

Question 4

What is a LDR?

Answer 4

a semi conductor whose resistance changes as the amount of light falling on its changes.

Question 5

Resistance triangle?

Answer 5

^
    / V  \
  / \_\_\_ \
 / I   | R  \
/\_\_\_|\_\_\_\

Question 6

What is a commutator?

Answer 6

A device for reversing the current dirrection through an armature every half turn.

Question 7

Why do we need friction?

Answer 7

• between our shoes and on the floor to keep us from slipping.
• between tyres and the road stop cares from skidding.
• between the brakes and the wheel to help bikes and cars slow down.