FOLLOW US ON TWITTER
SHARE THIS PAGE ON FACEBOOK, TWITTER, WHATSAPP ... USING THE BUTTONS ON THE LEFT


YOUR PARTICIPATION FOR THE GROWTH OF PHYSICS REFERENCE BLOG

Thursday, March 14, 2019

The Atlantic torpedo is a large electric fish capable of generating a voltage of 220 V between its tail and its head.


Question 7
The Atlantic torpedo is a large electric fish capable of generating a voltage of 220 V between its tail and its head. This drives a pulse of current of 15 A lasting for a time of 2.0 ms. The fish produces 200 pulses per second.

What is the average power output of the fish?
A 33 W                        B 1.3 kW                     C 3.3 kW                     D 6.6 kW





Reference: Past Exam Paper – November 2015 Paper 11 Q33





Solution:
Answer: B.

A pulse of current of 15 A lasts for 2.0 ms.

Power = VI                 and Power = Energy / time
Energy = Power × time

Energy of each pulse = VIt
Energy of each pulse = 220 × 15 × 2.0×10-3 = 6.6 J

The fish produces 200 pulses per second (this quantity is the number of pulses per second).

Average power = total energy / time
Average power = no. of pulses × energy of 1 pulse / time
Average power = (no. of pulses / time) × energy of 1 pulse

(no. of pulses / time) = 200 s-1

Average power = (no. of pulses / time) × energy of 1 pulse
Average power = 200 × 6.6
Average power = 1320 W = 1.3 kW

No comments:

Post a Comment

If it's a past exam question, do not include links to the paper. Only the reference.
Comments will only be published after moderation

Currently Viewing: Physics Reference | The Atlantic torpedo is a large electric fish capable of generating a voltage of 220 V between its tail and its head.