A pacemaker uses an RC circuit for timing. (a) If the pacemaker is to operate at 72 beats/min,
and if the circuit “fires” when the capacitor is 65%
charged, what must the time constant be?
(b) When C 5 7.50 mF, what value of resistance should
be used?

The boat's velocity relative to the riverbank can be resolved into two components. the component going north is 2.7 m/s and the component going west is 1.2 m/s.we add these two vectors and then find the magnitude of the resultant to get the speed.the magnitude of the resultant vector from adding can be obtained by the pythagorean theorem.    to two significant figures, the boat's speed relative to the riverbank is 3.0 m/s.

Dformation of a precipitate