This looks like the photo electric effect ... classical physics reckoned that if you shone an intense enough light beam on a metal you could get electrons ejected from the metal (maybe in analogy to thermionic emission - heat). It sort of "forgot" about the frequency and photon/particle nature of light.
Enter the "photo electric" effect experiment, Einstein's explanation, and the Nobel committee having an excuse to award E a Nobel prize, even though said prize was probably more for relativity.
Answer:
(A) = 3.57 m
Explanation:
from the question we are given the following:
diameter (d) = 3.2 m
mass (m) == 42 kg
angular speed (ω) = 4.27 rad/s
from the conservation of energy
mgh = 0.5 mv^{2} + 0.5Iω^{2} ...equation 1
where
Inertia (I) = 0.5mr^{2}
ω = \frac{v}{r}
equation 1 now becomes
mgh = 0.5 mv^{2} + 0.5(0.5mr^{2})(\frac{v}{r})^{2}
gh = 0.5 v^{2} + 0.5(0.5)(v)^{2}
4gh = 2v^{2} + v^{2}
h = 3v^{2} ÷ 4 g .... equation 2
from ω = \frac{v}{r}
v = ωr = 4.27 x (3.2 ÷ 2)
v = 6.8 m/s
now substituting the value of v into equation 2
h = 3v^{2} ÷ 4 g
h = 3 x (6.8)^{2} ÷ (4 x 9.8)
h = 3.57 m
Answer:
Explanation:
When a pair of medial has greater difference between the their individual refractive indices with respect to vacuum then it has a greater deviation between the refracted ray and the incident ray.
According to the Snell's law:
a)
b)
c)
d)
e)
f)
Answer:
a) t = 1.8 x 10² s
b) t = 54 s
c) t = 49 s
Explanation:
a) The equation for the position of an object moving in a straight line at constan speed is:
x = x0 + v * t
where
x = position at time t
x0 = initial position
v = velocity
t = time
In this case, the origin of our reference system is at the begining of the sidewalk.
a) To calculate the time the passenger travels on the sidewalk without wlaking, we can use the equation for the position, using as speed the speed of the sidewalk:
x = x0 + v * t
95 m = 0m + 0. 53 m/s * t
t = 95 m/ 0.53 m/s
t = 1.8 x 10² s
b) Now, the speed of the passenger will be her walking speed plus the speed of th sidewalk (0.53 m/s + 1.24 m/s = 1.77 m/s)
t = 95 m/ 1.77 m/s = 54 s
c) In this case, the passenger is located 95 m from the begining of the sidewalk, then, x0 = 95 m and the final position will be x = 0. She walks in an opposite direction to the movement of the sidewalk, towards the origin of the system of reference ( the begining of the sidewalk). Then, her speed will be negative ( v = 0.53 m/s - 2*(1.24 m/s) = -1.95 m/s. Then:
0 m = 95 m -1.95 m/s * t
t = -95 m / -1.95 m/s = 49 s
