Answer:
4. Electrons move from higher energy states to lower energy states.
Explanation:
When electrons fall from a higher (excited) energy state to a lower energy state, it loses/gives out energy.
This energy is given out by the emission of photons (quanta of light) by the electron.
Without an atmosphere, the equatorial curve would show minimum daily values on the solstices in June when the sub-solar point is located at 23.5°N and in December when the sub-solar point is at 23.5°S latitude.
Explanation:
At the sub-solar point, the sun strikes directly at the surface with an angle of 90 degrees at a given point.
Solistice refers to that point in time when the sun’s zenith is located at the farthest point from the equator.
During summer solistice on June 21, the sun’s zenith reaches northernmost point, sub-solar point is fixed at 23.5°S Tropic of Cancer making the earth tilt 23.4 degrees
During winter soliscitse on December 21, the sub-solar point is fixed at) Tropic of Capricorn.
Answer:
v= 1.71 m/s
Explanation:
Given that
Distance between two successive crests = 4.0 m
λ = 4 m
T= 7 sec
T is the time between 3 waves.
3 waves = 7 sec
1 wave = 7 /3 sec
So t= 7/3 s
We know that frequency f
f= 1/t= 3/7 Hz
Lets take speed of the wave is v
v= f λ
f=frequency
λ=wavelength
v= 3/7 x 4 = 12 /7
v= 1.71 m/s
Explanation:
Given that,
Mass if the rock, m = 1 kg
It is suspended from the tip of a horizontal meter stick at the 0-cm mark so that the meter stick barely balances like a seesaw when its fulcrum is at the 12.5-cm mark.
We need to find the mass of the meter stick. The force acting by the stone is
F = 1 × 9.8 = 9.8 N
Let W be the weight of the meter stick. If the net torque is zero on the stick then the stick does not move and it remains in equilibrium condition. So, taking torque about the pivot.

W = 3.266 N
The mass of the meters stick is :

So, the mass of the meter stick is 0.333 kg.
Answer:
0.231 m/s
Explanation:
m = mass attached to the spring = 0.405 kg
k = spring constant of spring = 26.3 N/m
x₀ = initial position = 3.31 cm = 0.0331 m
x = final position = (0.5) x₀ = (0.5) (0.0331) = 0.01655 m
v₀ = initial speed = 0 m/s
v = final speed = ?
Using conservation of energy
Initial kinetic energy + initial spring energy = Final kinetic energy + final spring energy
(0.5) m v₀² + (0.5) k x₀² = (0.5) m v² + (0.5) k x²
m v₀² + k x₀² = m v² + k x²
(0.405) (0)² + (26.3) (0.0331)² = (0.405) v² + (26.3) (0.01655)²
v = 0.231 m/s