Question 1
State the law of electrostatic charges
Answer
Like charges repel while unlike charges attract
Question 2
State one difference between a nickel cadmium (Nicd) cell and nickel – iron (NiFe) cell
Answer
Nickel cadmium (NiCd) cell can be stored charged while a Nickel – iron (NiFe) cannot
Question 3
Figure 1 shows a magnetic material being magnetized
Identify the polarities of X and Y
Answer
X – North pole;
Y – South pole;
Y – South pole;
Question 4
Two loudspeakers play the same note from a signal generator as shown in figure 2.
A person moves across the line between them. State with a reason what the person observes
Answer
- The person hears loud and soft sounds at alternate places;
- Loud sound is due to constructive interference and soft sounds due to destructive interference
- Loud sound is due to constructive interference and soft sounds due to destructive interference
Question 5
A lightning flash is seen, followed by thunder 6 seconds later. How far is the storm from the observer? Speed of sound = 340ms-1
Answer
Distance = Speed x Time
= 340mS-1 x 6s
= 2040m
= 340mS-1 x 6s
= 2040m