Calculus/velocity

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Expert: Alon Mandes - 1/2/2011


Question
a ball is thrown upward at a velocity of 100ft/s. the distance of the ball from the ground is f(t)=-16t^2+100t. find the instantaneous velocity at

a. 1 sec
b. at the top
c. at the bottom

Answer
The instantaneous velocity is defined as the derivative of f(t). Meaning :
V(t)=-32t+100 . Thus, V(1 sec)=68 ft/s .
At the top V=0 . When reaching the top the ball will switch direction , and fall back
to the ground, reaching the same velocity 100 ft/s , as it was thrown .
this can be seen also from the expression of the distance f(t) . It has 2 roots t=0 and
t=6.25 (this is the time that took the ball to reach the ground again) .
V(6.25 sec)=-23*6.25+100=100 ft/s .

Alon.

Calculus

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Alon Mandes

Expertise

Kind of questions I can answer : Limits, Derivatives, Integration, Implicit functions, continuousity, differentiation ,Extremum problems, Lagrange multipliers, Gradients, Surface integrals, Multi variables functions ,Multi variables Integrals,Complex variables ,Complex functions, Curves, Trajectory integrals & Vector analyse,Divergence,Rotor & word problems. Kind of question I can't answer : Economics,Combinatorics,infinite series & convergence ,Statistics & Probabilities .

Experience

1. I'm a team member of mathnerds (math site for answering questions) 2. I'm a team member in the Student's Union of the Technion, helping students who have problems in mathematics. 3. 2 years of experience as a math teacher in college. 4. I give free homework help for high school students in Mathematics & Physics. 5. I teach part time in collage the subjects : "Digital Signal Processing" , "Random Signals & Noise" , "Complex Functions".

Organizations
Hi-Tech company : GSM4VOIP ; job possition : Algorythm developer.

Education/Credentials
M.A in Mathematics & Bs.c in Electronics.

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