Answer:
The answer to your question is a = -1.85 m/s² the acceleration is negative because it is coming to stop.
Explanation:
Data
vo = 25 m/s
t = 13.5 s
a= ?
vf = 0 m/s
Formula
vf = vo + at
solve for a
a = (vf - vo)/t
Substitution
a = (0 - 25) / 13.5
Simplification
a = -25/13.5
Result
a = -1.85 m/s²
Answer:
215000kgm/s
Explanation:
Given parameters:
Mass of the moving body = 5000kg
Velocity = 43m/s
Unknown:
Momentum = ?
Solution:
The momentum of a body is the amount of motion a body possess.
It is mathematically expressed as:
Momentum = mass x velocity
Now:
Momentum = 5000 x 43 = 215000kgm/s
Answer:
64.945 miles per hour
Explanation:
Since the frequency of sound heard is higher than actual frequency, the ambulance is moving towards you!
The frequency of sound waves as heard from a distance for a sound wave coming towards one at v₀ m/s and whose real frequency is f₀ is given by
+f = f₀/[1 - (v₀/v)]
+f = frequency of sound as heard from the distance away = 8.61 KHz
f₀ = real frequency of sound = 7.87 KHz
v₀ = velocity at which the sound source is moving towards the reference point = ?
v = velocity of sound waves = 343 m/s
8.61 = 7.87/(1 - (v₀/v))
1 - (v₀/343) = 0.9141
v₀/343 = 1 - 0.9141 = 0.0859
v₀ = 343 × 0.0859 = 29.48 m/s = 64.945 miles per hour