The time it takes "to complete one cycle" is a perfect definition for <em>period</em>.
So the <em>2 sec</em> that you measured is the swing's period.
Frequency is just 1/period (the 'reciprocal' of the period).
For this swing, the frequency is 1/(2sec) = 0.5 per second = <em>0.5 Hz</em>.
( "Hertz" means "per second")
Answer:
A plane mirror is placed to the right of an object. The image formed by the mirror will be a virtual image that appears to be on the left of the mirror.
Explanation:
We can see it as two movements: one on the north-south axis and one on the west-east axis.
On the north-south Axis, the hiker went 8 km north and 4 km south, so in total the hiker went 4 km north (we can subtract one for the other and the direction remains that which was bigger)
On the west-easth Axis, the hiker went 6 km east and 6 km west, so in total the hiker didn't move on this axis! or, he/she moved but then "came back"
So in total, the hiker only moved4 km north - answer B.
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