We are given
r = 0.6 m
n = 1.5
D = 0.6 m, R1 = 30 cm
R2 = 120 cm
We are asked to get the focal length and the distance of the focal plane from the lens
We use the formula
1 / f = ( n - 1) (1/R1 - 1/R2)
Substituting and solving for f
1/ f = (1.5 - 1) (1/30 - 1/120)
f = 80 cm
The focal length is 80 cm and the distance of the focal plane from the lesn is 80 cm - 30 cm = 50 cm.<span />
Answer:
Newton's third law, if i'm not mistaken.
Explanation:
Any action that occurs will have a opposite and equal action. The greater the force u apply to the wall, the greater the force the wall exerts back at you, hence why ur hands become red if u try pushing extremely hard on the wall.
B. A sandbar is formed by water. A sand dune is formed by wind.
Answer:
the normal force on the rock acts perpendicular to the bowl's surface.
Explanation:
As we know that Normal force is the reaction force of two contact surfaces which always act perpendicular to the contact surfaces
Here we know that the rock is moving inside the bowl
So Normal force on the rock must perpendicular to the surface of the bowl which always passes through the center of the bowl.
Since the rock is moving in vertical plane so it must have two acceleration
1) Tangential acceleration which will increase the magnitude of the speed along the tangential path
2) Centripetal acceleration which will change the direction of the rock
So here only correct option will be
the normal force on the rock acts perpendicular to the bowl's surface.
Answer:
a) f = 4.76 10¹⁴ Hz, b) d = 2.73 10⁻⁴ m, c) θ = 6.923 10⁻³ rad
Explanation:
a) In this problem the frequency of light is asked, let's use the relationship between the speed of the wave, its wavelength and its frequency
c = λ f
f = c /λ
f = 
f = 4.76 10¹⁴ Hz
b) slit separation (d)
the expression for the constructive interference of the double-slit experiment is
d sin θ = m λ
let's use trigonometry
tan θ = y / L
tan θ = 
in general the angles are small, so we can approximate
tan θ = sin θ
tan θ = y/L
we substitute
d y / L = m λ
d = m L λ / y
we calculate
d = 3 1.3 630 10⁻⁹ /0.90 10⁻²
d = 2.73 10⁻⁴ m
c) the angle
tan θ = y / L
θ = tan⁻¹ y / L
θ = tan⁻¹ 0.9 10⁻² / 1.3
θ = tan⁻¹ 6,923 10⁻³
let's find the angle in radians
θ = 6.923 10⁻³ rad
