An angle of 60 degrees with the negative y-axis could mean 60 degrees clockwise or counterclockwise, which translates to two possible angles (starting from the positive x-axis and moving counterclockwise) of 210 degrees or 330 degrees.
Then the horizontal component 
of a velocity vector 
with magnitude 
could be one of two expressions:
Answer:
a. 5 batteries b. 1050 mAh
Explanation:
Here is the complete question
A student project is required to be portable and hand held. It requires 6 V DC power at a current of 150 mA. The batteries for the power supply must last for a minimum of 7 hours of continuous operation. NiMH rechargeable batteries in AA size are to be used. A) How many batteries are needed? B) What mAh capacity should the batteries have?
Solution
A) How many batteries are needed?
Since the nominal voltage for a single NiMH battery is 1.2 V per battery and we require 6V DC power, we combine the batteries in series to obtain a total voltage of 6 V. The number of batteries required, n = total voltage/voltage per cell = 6V/1.2V per battery = 5 batteries
So, the number of batteries needed is 5.
B) What mAh capacity should the batteries have?
Since the batteries are in series, they would each deliver a current of 150 mA. Since we require a current of 150 mA for 7 hours, the number of milliampere-hours capacity mAh of batteries required is Q = It where I = current = 150 mA and t = time = 7 hours.
So, Q = It = 150 mA × 7 h = 1050 mAh.
So, the batteries should have a mAh of 1050 mAh
Pollution is a giant sorce to global warming
Answer:
(a) 1133J/m
(b) 5.714m²
Explanation:
(a) u = 1/2×εE²
εo = 8.85×10-¹² F/m
E = 0.8 × 2.0×10⁷V/m = 1.6×10⁷V/m
u = 1/2×8.85×10-¹² × (1.6×10⁷)²= 1132.8J/m
(b)
U = 1/2CV² = 1/2(Aεo/d)×V²
U = 1/2(Aεo/d)×V²
U = 200mJ = 200×10-³
d = V/E = 500/ (1.6×10⁷) =3.13×10-⁵m
200×10-³ = 0.5×A×8.85×10-¹²×500²/3.13×10-⁵
200×10-³ = 0.035A
A = 200×10-³/ 0.035 = 5.714m².
Answer: Wavelength can be defined as the distance between two successive crests or troughs of a wave. It is measured in the direction of the wave.
Explanation:
Wavelength refers to the length or distance between two identical points of neighboring cycles of a wave signal traveling in space or in any physical medium. ... The wavelength of a signal is inversely proportional to its frequency, that is, the higher the frequency, the shorter the wavelength.
