It has both magnitude and direction
Answer:
d because the proton would move towards the negative plate
Explanation:
Answer:
網站有中、英文版本,也有繁、簡體版,可通過每頁左上角的連結隨時網站有中、英文版本,也有繁、簡體版,可通過每頁左上角的連結隨時
Explanation:
Answer:
Pi(3.14) radians or 180º degrees
Explanation:
First of all, we need to obtain the wavelength of a wave traveling to the speed of sound and 420 Hz of frequency.
The formula is:

where l = wavelength in meters
With current values:
l = 336 [m/s]/420[1/s] = 0.8 meters
Since a complete cycle (360º or 2pi radians) needs 0.8 meters to complete, 0.4 meters or 40 cm is just half of it, making a 180º degree phase or 3.14 radians.
Weight = (mass) x (local gravity)
8.2 N = (5 kg) x ( g )
Divide each side
by 5 kg : 8.2 N / 5 kg = g
g = (8.5 kg-m/s²) / (5 kg)
= (8.5 / 5) m/s²
= 1.7 m/s² .