Velocity - <span><span>the speed of something in a given direction
Speed - </span></span><span>rapidity in moving, going, traveling, proceeding, or performing; swiftness; <span>celerity
Velocity is the speed in a certain direction, whereas speed is just the rate of fastness.
Does that make sense?
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The strength of an electromagnet can be altered by increasing the number of coils around the core. The more times the coil is wrapped, the stronger the electromagnet is.
Your answer is: B) Increasing the number of coils around the core
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