Astudent is swinging a ball on a string overhead in a horizontal plane. the string initially has length l0 and the ball is moving with an initial speed v0 . the student decides to see how fast they can spin the ball, so they begin moving it faster and faster with a constant tangential acceleration at. however, they know that the string is close to breaking, so they decide to keep letting the string get longer and longer in order to keep the tension in the string constant. find expressions for the length of the string and the total acceleration (magnitude and direction) as a function of time, l0, v0, and at. you may ignore the effect of gravity on the ball.

nec chapter 5 contains

c. information on special occupancy areas

nec chapter 6 covers

a. special equipment

which of the following rules contain the words shall or shall not and must be adhered to?

b. mandatory rules

which of the following rules identify actions that are allowed but not required and typically cover options or alternative methods?

c. optional rules

which of the following serves as the introduction to the nec and provides an overview of the book?

a. nec article 90

organizations that test products for safety are

c. nrtls

the nec is published by the

a national fire protection association

the nec is divided into

b. 9 chapters

the nec provides informative annexes for

c. informational materials and examples

two terms from nec article 100 that trainees should become familiar with are

b. labeled and listed

explanation:

firearm identification is the process of analyzing the bullets and cartridge cases left at a crime scene to determine if they came from a particular firearm. marks on the bullets and cartridges may be common to every firearm of that type. these are called class characteristics.

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2