Answer:
<em>Magnetic</em><em> </em><em>compass</em><em> </em><em>helps</em><em> </em><em>to </em><em>identify</em><em> </em><em>direction</em><em> </em><em>in </em><em>this </em><em>way </em><em>,</em><em> </em><em>this </em><em>compass</em><em> </em><em>work </em><em>because</em><em> </em><em>of </em><em>earth</em><em> </em><em>magnetic</em><em> field</em><em> </em><em>and </em><em>show</em><em> </em><em>us </em><em>direction</em><em> </em>
<em> </em><em> </em><em>hope</em><em> it</em><em> helps</em><em> and</em><em> your</em><em> day</em><em> will</em><em> be</em><em> full</em><em> of</em><em> happiness</em><em>. </em>^_^
False because your deltoids are in your shoulders not your back
A). No. In fact, the longer you leave things hooked up like this, the weaker the battery becomes.
<em>B). Yes ! </em>As long as everything stays hooked up like this, the nail is a magnet. (Until the battery finally dies of exhaustion.)
C). No.
D). I don't think so. Never heard of this one.
Using Newton's law that F = ma.
The force here is the net force. The forces acting in opposite direction are the weight and the air resistance. The weight of course is acting downwards and the air resistance is pushing upwards.
Therefore:
W - AR = ma W = Weight = mg, AR = Air Resistance = 150.
g = 10 m/s2
mg - AR = ma
60(10) - 150 = 60a
600 - 150 = 60a
450 = 60a
60a = 450
a = 450/60
a = 7.5 m/s2
Cheers.