The quantity of charge \( Q \) in coulombs (C) that has passed through a point in a wire up to time \( t \) (measured in seconds) is given by \[ Q(t) = t^3 - 4t^2 + 7t + 4. \](a) Find the current when \( t = 0.7 \, \text{s} \). \[\boxed{\phantom{5}}\] A(b) Find the current when \( t = 1 \, \text{s} \). \[\boxed{\phantom{5}}\] AAt what time is the current the lowest? \( t = \boxed{\phantom{5}} \) s

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The quantity of charge Q in coulombs (C) that has passed through a point in a wire up to time t (measured in seconds) is given by Q(t) = t³ — 4t² + 7t + 4. (a) Find the current when t = 0.7 s. (b) Find the current when t = 1 s. At what time is the current the lowest? t =

The quantity of charge Q in coulombs (C) that has passed through a point in a wire up to time t (measured in seconds) is given by Q(t) = t³ — 4t² + 7t + 4. (a) Find the current when t = 0.7 s. (b) Find the current when t = 1 s. At what time is the current the lowest? t =

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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