The one that will change the velocity of a periodic wave is :
B. Changing the medium of the wave
Waves is always determined by the properties of the medium, which means that changing the medium will change the velocity of the wave
hope this helps
Answer:
The coil radius of other generator is 5.15 cm
Explanation:
Consider the equation for induced emf in a generator coil:
EMF = NBAω Sin(ωt)
where,
N = No. of turns in coil
B = magnetic field
A = Cross-sectional area of coil = π r²
ω = angular velocity
t = time
It is given that for both the coils magnetic field, no. of turn and frequency is same. Since, the frequency is same, therefore, the angular velocity, will also be same. As, ω = 2πft.
Therefore, EMF for both coils or generators will be:
EMF₁ = NBπr₁²ω Sin(ωt)
EMF₂ = NBπr₂²ω Sin(ωt)
dividing both the equations:
EMF₁/EMF₂ = (r₁/r₂)²
r₂ = r₁ √(EMF₂/EMF₁)
where,
EMF₁ = 1.8 V
EMF₂ = 3.9 V
r₁ = 3.5 cm
r₂ = ?
Therefore,
r₂ = (3.5 cm)√(3.9 V/1.8 V)
<u>r₂ = 5.15 cm</u>
Answer:
A. 1.4 m/s to the left
Explanation:
To solve this problem we must use the principle of conservation of momentum. Let's define the velocity signs according to the direction, if the velocity is to the right, a positive sign will be introduced into the equation, if the velocity is to the left, a negative sign will be introduced into the equation. Two moments will be analyzed in this equation. The moment before the collision and the moment after the collision. The moment before the collision is taken to the left of the equation and the moment after the collision to the right, so we have:
where:
M = momentum [kg*m/s]
M = m*v
where:
m = mass [kg]
v = velocity [m/s]
where:
m1 = mass of the basketball = 0.5 [kg]
v1 = velocity of the basketball before the collision = 5 [m/s]
m2 = mass of the tennis ball = 0.05 [kg]
v2 = velocity of the tennis ball before the collision = - 30 [m/s]
v3 = velocity of the basketball after the collision [m/s]
v4 = velocity of the tennis ball after the collision = 34 [m/s]
Now replacing and solving:
(0.5*5) - (0.05*30) = (0.5*v3) + (0.05*34)
1 - (0.05*34) = 0.5*v3
- 0.7 = 0.5*v
v = - 1.4 [m/s]
The negative sign means that the movement is towards left
I'm doing questions in grade 10 math working on imperial system how should I give my answers in decimals or fraction it's an adult learning experience
Answer:
Explanation:
given, work function of Φ = 2.46 eV.
converting the eV to joule, we have
2.45 * 1.6*10^-19 J
The cutoff wavelength is the wavelength where the incoming light does not have enough energy to free an electron, i.e. all of
the photon’s energy will be channeled into trying overcoming the work function barrier.
It is mathematically given as
Φ = hf
f = Φ/h
f = (2.46 * 1.6*10^-19) / 6.63*10^-34
f = 3.936*10^-19 / 6.63*10^-34
f = 5.94*10^14 Hz as our cut off frequency
λf = c,
λ = c/f
λ = 3*10^8 / 5.94*10^14
λ = 5.05*10^-7
λ = 505 nm as our cut off wavelength
K(max) = hf - Φ
K(max) = hc/λ - Φ
K(max) = [(6.63*10^-34 * 3*10^8) / 181*10^-9] - 3.936*10^-19
K(max) = (1.989*10^-25/181*10^-9) - 3.936*10^-19
K(max) = 1.1*10^-18 - 3.936*10^-19
K(max) = 7.064*10^-19 J or 4.415 eV
V(s) = K(max) / e
V(s) = 4.612 V