Let us assume the upstream rowing rate of Alicia = x
Let us assume the downstream rowing rate of Alicia = y
We already know that
Travelling time = Distance traveled/rowing rate
Then
6/(x + 3) = 4/x
6x = 4x + 12
6x - 4x = 12
2x = 12
x = 6
Then
Rowing rate of Alicia going upstream = 6 miles per hour
Rowing rate of Alicia going downstream = 9 miles per hour.
I don't know about it your answer will give another people
m = mass of the car moving in horizontal circle = 1750 kg
v = Constant speed of the car moving in the horizontal circle = 15 m/s
r = radius of the horizontal circular track traced by the car = 45.0 m
F = magnitude of the centripetal force acting on the car
To move in a circle . centripetal force is required which is given as
F = m v²/r
inserting the above values in the formula
F = (1750) (15)²/(45)
F = (1750) (225)/(45)
F = 1750 x 5
F = 8750 N
Answer:
Explanation:
It is given that,
The number of lines per unit length, N = 900 slits per cm
Distance between the formed pattern and the grating, l = 2.3 m
n the first-order spectrum, maxima for two different wavelengths are separated on the screen by 2.98 mm, 
Let d is the slit width of the grating,
For the first wavelength, the position of maxima is given by :
For the other wavelength, the position of maxima is given by :
So,
or
So, the difference between these wavelengths is 14.3 nm. Hence, this is the required solution.
