Answer:
D. in a closed system, an object's momentum before a collision will equal its momentum after the collision.
Explanation:
As we know by newton's II law we have

so we will have
F = net force on the system
= change in momentum
so we can say if the momentum is conserved or the initial momentum of the system will be equal to the final momentum of the system
then we will say that

so net force on the system must be ZERO
so in such type of questions the system must be isolated and there is no external force on it
so correct answer will be
D. in a closed system, an object's momentum before a collision will equal its momentum after the collision.
Answer: 56.44°
Explanation:
<u>Given:</u>
- Let u represent the current speed of the plane, <u>1.2 Mach</u>
<em>Converting to SI Units (m/s):</em>
= (1.2 mach)(340 ms^-1 / 1 Mach)
u = 408 m/s
- Speed of sound in air, v = 340 m/s
<u>Find:</u>
- Angle the wave front of the shock wave relative to the plane's direction of motion, θ
We have, sinθ = speed of sound / speed of object
sinθ = v / u
θ = sin^-1 (v / u)
= sin^-1 (340 / 408)
θ = 56.44°
The answer is A. Trust me!