Answer:
New Resistance = 0.5556 ohm
Explanation:
Resistance = resistivity * length /area
Here since resistivity and length are constant, we only need to see how the resistance increases or decreases with change in area.
New Area = pi * (3*D)^2 / 4
Old Area = pi * D^2 / 4
The ratio of new area / old area is :

Since area increases 9 times, and it is inversely proportional to resistance:
Resistance decreases by 9 times.
So, old resistance = Voltage / Current = 10 / 2 = 5 ohm
New Resistance = 5 / 9 = 0.5556 ohm (decreases by 9 times)
Explanation:
We know that the relation between volume and density is as follows.
Volume = 
So, V = 
= 
Now, we will calculate the area as follows.
Area = 
= 
= 
Formula to calculate the resistance is as follows.
R = 
= 
= 
Thus, we can conclude that the resistance of given wire is
.
About 13.7 billion years ago
The Big Bang Theory states that the universe started about 13.7 billion years ago, and before that, everything was in 1 singularity.
Answer:
smaller one
Explanation:
even though he is moving quicker doesn't mean he will be packing more force in the collision
Answer:
Explanation:
Work done by the spring is negative .
Work done by force F creating displacement d is given by the following expression .
Work = F x d
Both force and displacement are vector quantity .
When direction of force and direction of displacement is same , work is positive . When direction of force and direction of displacement is opposite , work is negative .
When spring is compressed , it exerts a restoring or opposing force in a direction opposite to the direction of displacement of box . Hence here force is opposite to displacement . Restoring force acts opposite to displacement . Hence work done by spring on box is negative .