Λ = 3*10^8 / 9*10^8 = 1/3 m
no. of wavelengths = 60/(1/3) = 180
Answer:
Coal and oil release sulfur dioxide gas when they burn, which causes breathing problems for living creatures and contributes to acid rain. Fossil fuels release carbon dioxide when they burn, which adds to the greenhouse effect and increases global warming .
Explanation:
Answer:
ω = 0.1 rad/s
v = 0.002 m/s
Explanation:
The angular velcoity of the second hand of the clock can be found by:
ω = θ/t
where,
ω = Angular Speed
θ = Angular Displacement
t = time taken
Now, for one complete revolution of second hand of the clock:
θ = 2π rad
t = 60 s
Therefore,
ω = 2π rad/60 s
<u>ω = 0.1 rad/s</u>
Now, for the linear speed (V):
V = rω
where,
V = Linear Speed of Second Hand = ?
r = radius = length of second hand = 0.02 m
Therefore,
V = (0.02 m)(0.1 rad/s)
<u>V = 0.002 m/s</u>
Answer:
Using 3 periods to get an accurate reading:
3T = (6.40 S - 0.90 s) = 5.50 S So, T = 1.83 s
m = 0.250 kg
Using algebra:
k= 
=
=2.95kg/sec
Answer:
Vi = 24.14 m/s
Explanation:
If we apply Law of Conservation of Energy or Work-Energy Principle here, we get: (neglecting friction)
Loss in K.E of the Rock = Gain in P.E of the Rock
(1/2)(m)(Vi² - Vf²) = mgh
Vi² - Vf² = 2gh
Vi² = Vf² + 2gh
Vi = √(Vf² + 2gh)
where,
Vi = Rock's Speed as it left the ground = ?
Vf = Final Speed = 17 m/s
g = 9.8 m/s²
h = height of rock = 15 m
Therefore,
Vi = √[(17 m/s)² + 2(9.8 m/s²)(15 m)]
Vi = √583 m²/s²
<u>Vi = 24.14 m/s</u>
