Answer:
because it weighs more than water
Number 3.
When you have two parallel wire and the charges are moving, they create a magnetic field around the wire (right-hand rule, thumb points in the direction of current).
If you want the math, here ya go:

F: magnetic force on the wire, L: length of the wire I: current in one wire I': current in other wire r: distance of the wire.
As we can see, two wires that has current through it will generate a force on each other.
A :-) for this question , we should apply
a = v - u by t
Given - u = -2 m/s
v = -10 m/s
t = 16 sec
Solution -
a = v - u by t
a = -10 - -2 by 16
a = -12 by 16
( cut 12 and 16 because 2 x 6 = 12 and
2 x 8 = 16 )
( cut 6 and 8 because 2 x 3 = 6 and
2 x 4 = 8 )
a = 3 by 4
a = 0.75 m/s^2
.:. The acceleration is 0.75 m/s^2.
0.119cm/s is the radius of the balloon increasing when the diameter is 20 cm.
<h3>How big is a circle's radius?</h3>
The radius of a circle is the distance a circle's center from any point along its circumference. Usually, "R" or "r" is used to indicate it.
A circle's diameter cuts through the center and extends from edge to edge, in contrast to a circle's radius, which extends from center to edge. Essentially, a circle is divided in half by its diameter.
dv/dt = 150cm³/s
d = 2r = 20cm
r = 10cm
find dr/dt
Given that the volume of a sphere is calculated using
v = 4/3πr³
Consider both sides of a derivative
d/dt(v) = d/dt( 4/3πr³)
dv/dt = 4/3π(3r²)dr/dt = 4πr²dr/dt
Hence,
dr/dt = 1/4πr².dv/dt
dr/dt = 1/4π×(10)²×150
dr/dt = 1/4π×100×150
dr/dt = 0.119cm/s.
To know more about radius visit:
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