Answer:
The efficiency of the system is 63.7 %
Explanation:
Given;
input power of the motor, = 1.5 kW = 1,500 W
mass of the car lifted, m = 1300 kg
height through which the car was lifted, h = 1.8 m
time, t = 24 s
The output power of the motor is calculated as;
Output Power = F x v
= (mg) x (d/t)
= (1300 x 9.8) x (1.8 / 24)
= 12,740 x 0.075
= 955.5 W
The efficiency of the system is calculated as;
The correct answer is 63.7%
Answer:
It would point up.
Explanation:
Since I am at the earth's geographic north magnetic pole, the place on the earth's surface that compasses point toward, the north pole of the compass would also point towards the earth's geographic north magnetic pole, since all other compasses point toward there.
Since the compass is free to swivel in any direction, the compass would point up, since it is at the earth's geographic north magnetic pole, the place on the earth's surface that compasses point toward.
So, the compass would point up.
If you search that click the first link ;)
λ - wavelength, c - the speed of light, f - frequency
![f=200 \ kHz= 200 000 \ Hz \\ \\ \lambda=\frac{300 000 \ [\frac{km}{s}]}{200 000 \ [Hz]}=\frac{3}{2}=1.5 \ [km]](https://tex.z-dn.net/?f=f%3D200%20%5C%20kHz%3D%20200%20000%20%5C%20Hz%20%5C%5C%20%5C%5C%0A%5Clambda%3D%5Cfrac%7B300%20000%20%5C%20%5B%5Cfrac%7Bkm%7D%7Bs%7D%5D%7D%7B200%20000%20%5C%20%5BHz%5D%7D%3D%5Cfrac%7B3%7D%7B2%7D%3D1.5%20%5C%20%5Bkm%5D)
The wavelength of these waves is 1.5 km.
