Answer:
915 Hz
Explanation:
The observed frequency from a sound source is given as
f₀ = f [(v + v₀)/(v+vₛ)]
where
f₀ = observed frequency of the sound by the observer = ?
f = actual frequency of the sound wave = 983 Hz
v = actual velocity of the sound waves = 343 m/s
vₛ = velocity of the source of the sound waves = 55.9 m/s
v₀ = velocity of the observer = 28.4 m/s
f₀ = 983 [(343+28.4)/(343+55.9)]
f₀ = 915.2 Hz = 915 Hz
The answer is B
second law
Answer:
Explanation:
We shall apply law of conservation of momentum .
Momentum before collision = momentum after collision .
Momentum before collision = 400 kg m/s
Momentum after collision = 5 x v + 11 x 15
where v is velocity of A after the collision .
5 x v + 11 x 15 = 400
5 v = 400 - 165
5v = 235
v = 47 m /s .
Answer:
Explanation:
Givens
Vi = 10 m/s
Vf = 40 m/s
a = 3 m/s^2
Formula
a = (vf - vi) /t Substitute the givens into this formuls
Solution
3 = (40 - 10) / t Multiply both sides by t
3*t = t(40 - 10)/t Combine. Cancel t's on the right
3*t = 30 Divide by 3
3t/3 = 30 / 3
Answer: t = 10 seconds.
Answer:
6.0 × 
W/
Explanation:
From Wien's displacement formula;
Q = e A
Where: Q is the quantity of heat transferred, e is the emissivity of the surface, A is the area, and T is the temperature.
The emissive intensity = 
= e
Given from the question that: e = 0.6 and T = 1000K, thus;
emissive intensity = 0.6 × 
= 0.6 × 1.0 × 
= 6.0 × 
Therefore, the emissive intensity coming out of the surface is 6.0 × W/.
