The pitch of a sound is decreased, when a sound source approaches the observer.
<u>Explanation:</u>
Pitch is nothing but it is a property that helps to determine whether the sound is high or low. Doppler effect helps to understand this concept easily. The pitch of the sound is mainly calculated based on the frequency of the sound wave arose from the sound source.
As the wellspring of sound waves moves toward an audience, the sound waves draw nearer together, expanding their recurrence and the pitch of the sound.
Answer:
4 m/s
Explanation:
From the law of conservation of momentum,
Total momentum before collision = Total momentum after collision
mu+m'u' = V(m+m')...................... Equation 1
Where m = mass of the arrow, u = initial velocity of the arrow, m' = mass of the apple, u' = initial velocity of the apple, V = Final velocity of the apple and the arrow after collision.
make V the subject of the equation
V = (mu+m'u')/(m+m').................... Equation 2
Given: m = 0.5 kg, m' = 2 kg, u = 20 m/s, u' = 0 m/s(initially at rest)
Substitute into equation 2
V = (0.5×20+2×0)/(2+0.5)
V = 10/2.5
V = 4 m/s.
Hence the final velocity of the apple and the arrow after the collision = 4 m/s
Answer:
Explanation:
Let the bullets speed be V .
Kinetic energy = 1/2 mV² where m is mass of bullet
This energy is converted into heat Q which raises the temperature of target by Δ T .
Q = mc Δ T , m is mass , c is specific heat and Δ T is rise in temperature .
heat absobed by bullet
= .0075 x 130 x .040
= .039 J
heat absorbed by block of wood
= 17.5 x 1700 x .04
= 1190 J
Total heat absorbed
= 1190.039 J
So kinetic energy = heat absobed
= 1/2 x .0075 x V² = 1190.039
V² = 317343.73
V = 563.33 m /s
