Let
be the direction the swimmer must swim relative to east. Then her velocity relative to the water is

The current has velocity vector (relative to the Earth)

The swimmer's resultant velocity (her velocity relative to the Earth) is then


We want the resultant vector to be pointing straight north, which means its horizontal component must be 0:

which is approximately 41º west of north.
Answer:
minimum power should be used to operate the air conditioner is 4000 W
Explanation:
given data
students n = 160
power p = 125 W
COP = 5.0
to find out
what minimum power should be used
solution
we know the COP formula that is given below
COP = students × power / minimum power
minimum power = n × p / COP
put all value
minimum power = n × p / COP
minimum power = 160 × 125 / 5
minimum power = 4000 W
minimum power should be used to operate the air conditioner is 4000 W
Answer:
Explanation:
i = Imax sin2πft
given i = 180 , Imax = 200 , f = 50 , t = ?
Put the give values in the equation above
180 = 200 sin 2πft
sin 2πft = .9
sin2π x 50t = .9
sin 360 x 50 t = sin ( 360n + 64 )
360 x 50 t = 360n + 64
360 x 50 t = 64 , ( putting n = 0 for least value of t )
18000 t = 64
t = 3.55 ms .