Answer:
Explanation:
a )
from lens makers formula
f is focal length , r₁ is radius of curvature of one face and r₂ is radius of curvature of second face
putting the values
1.462 = 2 - 1 / r₂
1 / r₂ = .538
r₂ = 1.86 cm .
= 18.6 mm .
b )
object distance u = 25 cm
focal length of convex lens f = 1.8 cm
image distance v = ?
lens formula
.5555 - .04
= .515
v = 1.94 cm
c )
magnification = v / u
= 1.94 / 25
= .0776
size of image = .0776 x size of object
= .0776 x 10 mm
= .776 mm
It will be a real image and it will be inverted.
<span>Two plastic balls suspended by strings are placed close to each other. If they have the same charge then they will repel each other.</span>
Answer:
T = 693.147 minutes
Explanation:
The tank is being continuously stirred. So let the salt concentration of the tank at some time t be x in units of kg/L.
Therefore, the total salt in the tank at time t = 1000x kg
Brine water flows into the tank at a rate of 6 L/min which has a concentration of 0.1 kg/L
Hence, the amount of salt that is added to the tank per minute = 
Also, there is a continuous outflow from the tank at a rate of 6 L/min.
Hence, amount of salt subtracted from the tank per minute = 6x kg/min
Now, the rate of change of salt concentration in the tank = 
So, the rate of change of salt in the tank can be given by the following equation,
or, 
or, T = 693.147 min (time taken for the tank to reach a salt concentration
of 0.05 kg/L)
In triangle ABC , using Pythagorean theorem
BC = sqrt(AB² + AC²)
r = sqrt(y² + x²) eq-1
taking derivative both side relative to "t"
dr/dt = (1/(2 sqrt(y² + x²) ) ) (2 y (dy/dt) + 2 x (dx/dt))
dr/dt = (1/(2 sqrt(0.5² + 0.5²) ) ) (2 (0.5) (dy/dt) + 2 (0.5) (dx/dt))
dr/dt = (1/(2 sqrt(0.5² + 0.5²) ) ) ( v₁ + v₂)
15= (1/(2 sqrt(0.5² + 0.5²) ) ) ( - 30 + v₂)
v₂ = 51.2 m/s
Answer:
141 m at 65.6° N of E
Explanation:
Let E be along the positive x axis of a unit circle
N = 90°
E = 0°
SE = -45°
W = 180°
NW = 135°
east displacement
x = 140cos90 + 85cos0 + 35cos-45 + 38cos180 + 19cos135 = 58.313708... m
north displacement
y = 140sin90 + 85sin0 + 35sin-45 + 38sin180 + 19sin135 = 128.6862915... m
d = √(128.6862915² + 58.313708²) = 141.28216525... m
tanθ = 128.6862915 / 58.313708
θ = 65.622521...
