Answer:
flagpole
Explanation:
if it is about electricity then its flagpole
Answer:
S = 11.025 m
Explanation:
Given,
The time taken by the pebble to hit the water surface is, t = 1.5 s
Acceleration due to gravity, g = 9.8 m/s²
Using the II equations of motion
S = ut + 1/2 gt²
Here u is the initial velocity of the pebble. Since it is free-fall, the initial velocity
u = 0
Therefore, the equation becomes
S = 1/2 gt²
Substituting the given values in the above equation
S = 0.5 x 9.8 x 1.5²
= 11.025 m
Hence, the distance from the edge of the well to the water's surface is, S = 11.025 m
Answer:
Explanation:
b ) First is concave lens with focal length f₁ = - 12 cm .
object distance u = - 20 cm .
Lens formula
1 / v - 1 / u = 1 / f
1 / v + 1 / 20 = -1 / 12
1 / v = - 1 / 20 -1 / 12
= - .05 - .08333
= - .13333
v = - 1 / .13333
= - 7.5 cm
first image is formed before the first lens on the side of object.
This will become object for second lens
distance from second lens = 7.5 + 9 = 16.5 cm
c )
For second lens
object distance u = - 16.5 cm
focal length f₂ = + 12 cm ( lens is convex )
image distance = v
lens formula ,
1 / v - 1 / u = 1 / f₂
1 / v + 1 / 16.5 = 1 / 12
1 / v = 1 / 12 - 1 / 16.5
= .08333- .0606
= .02273
v = 1 / .02273
= 44 cm ( approx )
It will be formed on the other side of convex lens
distance from first lens
= 44 + 9 = 53 cm .
magnification by first lens = v / u
= -7.5 / -20 = .375 .
magnification by second lens = v / u
= 44 / - 16.5
= - 2.67
d )
total magnification
= .375 x - 2.67
= - 1.00125
height of final image
= 2.50 mm x 1.00125
= 2.503mm
e )
The final image will be inverted with respect to object because total magnification is negative .
Answer:
295.42 N
Explanation:
From Newton's law of universal gravitation.
F = Gmm'/r².................. Equation 1
Where F = Gravitational force, G = Universal constant, m = mass of the human, m' = mass of mass, r = radius of mass.
Given: m = 80 kg, m' = 6.4×10²³ kg, r = 3.4×10⁶ m.
Constant: G = 6.67×10⁻¹¹ Nm²/Kg²
Substitute into equation 1
F = 6.67×10⁻¹¹(80)(6.4×10²³ )/( 3.4×10⁶)²
F = 3415.04×10¹²/(11.56×10¹²)
F = 3415.04/11.56
F = 295.42 N
Hence the gravitational force = 295.42 N
Fnet=(115+106)-186= 34 N
mass=Force/g= 186N/9.8m/s^2 = 18.98 kg
a=fnet/mass => 34N/18.98kg = 1.79 m/s^2
so A= 1.8m/s^2
