consider east-west direction along X-axis and north-south direction along Y-axis
= velocity of migrating robin relative to air = 12 j m/s
(where "j" is unit vector in Y-direction)
= velocity of air relative to ground = 6.3 i m/s
(where "i" is unit vector in X-direction)
= velocity of migrating robin relative to ground = ?
using the equation
= +
= 12 j + 6.3 i
= 6.3 i + 12 j
magnitude : sqrt((6.3)² + (12)²) = 13.6 m/s
direction : tan⁻¹(12/6.3) = 62.3 deg north of east
Answer:
she's wrong because she is and there it doesn't say she's right
Answer:
The car must be moving away from the person.
Explanation:
From Doppler's Effect, we know that when a sound source moves towards a stationary observer, the apparent frequency of that sound increases. While the apparent frequency decreases if the source moves away from the stationary observer.
The audible range of frequencies for a human ear is 20 Hz to 20000 Hz. Therefore, in order for the sound of a loud speaker to be audible for the person, the frequency must decrease below 20000 Hz.
<u>Due to this reason, the car must be moving away from the person.</u>
Work is (force applied) x (distance through which the force moves).
Since the suitcase doesn't move up or down during the 15 minutes,
no work is done ... zero, zip, nada ... according to the real Physics
definition of 'work'.
