The answer using the graphical method and analytical method of vector addition will always be
C. Same
Analytic method means adding vectors (x₁,y₁) and (x₂,y₂) give (x₁+x₂,y₁+y₂)
Example: Addition of (2,3) and (1,1) gives (3,4)
Solving it graphically will also give (3,4)
Answer:
The human ear is not sensitive to every frequency of sound, rather, our hearing range is from 20Hz to 20,000Hz. This means sound frequencies outside this range are not audible to the human ear, which is why not every sound produced is heard. This is quite a blessing because if we could hear every vibrating body, then our ears would never stop listening: we won't be able to distinguish 'important sounds' from unimportant ones, rendering our ears effectively useless. Perhaps this is why we have a hearing range in the first place: sounds of our friends and our foes lie in 20Hz-20kHz range.
The kinetic energy of an object of mass m moving with speed v is given by:
For the bicycle in our problem,
and
, so the kinetic energy is
The complete question is how much heat energy is delivered by the iron in 30 seconds.
Heat is given by IVt, Where I is the current in Amperes, V is the voltage, and t is the time in seconds,
Therefore;
Heat energy = 120 × 10 ×30
= 36000 joules or 36 kJ
Heat energy is measured in joules.
