Different wavelengths of light are seen as colors
Answer:
5.4
Explanation:
900/10=90 and 90(60)=5400 meters. 5400/100=5.4
Answer:
6.4 J
Explanation:
m = mass of the bullet = 10 g = 0.010 kg
v = initial velocity of bullet before collision = 1.8 km/s = 1800 m/s
v' = final velocity of the bullet after collision = 1 km/s = 1000 m/s
M = mass of the block = 5 kg
V = initial velocity of block before collision = 0 m/s
V' = final velocity of the block after collision = ?
Using conservation of momentum
mv + MV = mv' + MV'
(0.010) (1800) + (5) (0) = (0.010) (1000) + (5) V'
V' = 1.6 m/s
Kinetic energy of the block after the collision is given as
KE = (0.5) M V'²
KE = (0.5) (5) (1.6)²
KE = 6.4 J
Answer:
Explanation:
The question relates to Doppler effect and beat.
The observer is moving towards the reflected sound so apparent frequency will be increased
f = f₀ x (V + v₁) / (V - v₂)
f is apparent frequency , f₀ is real frequency , V is velocity of sound , v₁ is velocity of observer and v₂ is velocity of source . Here
v₁ = v₂ = vp as both observer and source have same velocity
f = f₀ x (V + v₁) / (V - v₂)
205 +5 = 205 x (344 +vp)/ ( 344 - vp)
1.0234 = (344 +vp)/ ( 344 - vp)
= 352 - 1.0234vp = 340+vp
12 / 2.0234vp
vp = 6 m /s approx.
