Answer:
a) The car was moving at a speed of 
b) The negative sign of
denotes that the observer is coming towards the police car which is the source of the sound.
c) 
Explanation:
Given:
- original frequency of the source,

- speed of the source,

- velocity of the obstacle car be,

- speed of sound,

- observed frequency,

<u>Using the equation from the Doppler's effect:</u>



a)
The car was moving at a speed of 
b)
The negative sign of
denotes that the observer is coming towards the police car which is the source of the sound.
c)
Now when, 
Then, 
Using the Doppler's eq.:


Answer:
x = 11.23 m
Explanation:
For this interesting exercise, we must use angular kinematics, linear kinematics and the relationship between angular and linear quantities.
Let's reduce to SI system units
θ = 155 rev (2pi rad / rev) = 310π rad
α = 2.00rev / s2 (2pi rad / 1 rev) = 4π rad / s²
Let's look for the angular velocity at the time the piece is released, with starting from rest the initial angular velocity is zero (wo = 0)
w² = w₀² + 2 α θ
w =√ 2 α θ
w = √(2 4pi 310pi)
w = 156.45 rad / s
The relationship between angular and linear velocity
v = w r
v = 156.45 0.175
v = 27.38 m / s
In this part we have the linear speed and the height that it travels to reach the floor, so with the projectile launch equations we can find the time it takes to arrive
y =
t - ½ g t²
As it leaves the highest point its speed is horizontal
y = 0 - ½ g t²
t = √ (-2y / g)
t = √ (-2 (-0.820) /9.8)
t = 0.41 s
With this time we calculate the horizontal distance, because the constant horizontal speed
x = vox t
x = 27.38 0.41
x = 11.23 m
Answer:
1.5 kgms⁻¹
Explanation:
Momentum can be defined as "<em>mass in motion</em>."
The amount of momentum that an object has is dependent upon two factors
- mass of the moving object
when there is a change in the velocity , it creates a change in momentum also
when we consider that we can mathematically show this,In terms of an equation,
Change in momentum (ΔΡ) = m(Δv)
where (Δv) - change in velocity
<em>(Δv) = final velocity - initial velocity</em>
Change in momentum (ΔΡ) = m(Δv)
= 0.1×([55-40])
= 1.5 kgms⁻¹
Kinetic energy is related to velocity by:
KE = (1/2)mv^2
solve for mass m
10 = (1/2)m(10)^2
10 = (1/2)m(100)
10= 50m
10/50 = m
1/5 = m
at 20 km/hr
KE = (1/2)(1/5)(20)^2
KE = (1/10)(400)
KE = 40 J
Answer:


Explanation:
Given Data:
Numbers of times Telescope cycled around the earth in 6 years=37,000 times
Total Distance traveled in 6 years by the Hubble Space Telescope=1,280,000,000 Km
Find:
Kilometers in one Orbit=?
Solution:
Kilometers in 37,000 Orbits=1,280,000,000 Km
Kilometers in 1 Orbit=1,280,000,000/37,000
In Scientific Notation:


Kilometers in 1 Orbit=34594.594 Km
Kilometers in 1 Orbit in Scientific notation:
