All categories

3 years ago

A stationary siren creates an 894 Hz

Physics

1 answer:

valentina_108 [34]3 years ago

5 0

Answer:

12.3 m/s

Explanation:

The Doppler equation describes how sound frequency depends on relative velocities:

fr = fs (c + vr)/(c + vs),

where fr is the frequency heard by the receiver,

fs is the frequency emitted at the source,

c is the speed of sound,

vr is the velocity of the receiver,

and vs is the velocity of the source.

Note: vr is positive if the receiver is moving towards the source, negative if away.

Conversely, vs is positive if the receiver is moving away from the source, and negative if towards.

Given:

fs = 894 Hz

fr = 926 Hz

c = 343 m/s

vs = 0 m/s

Find: vr

926 = 894 (343 + vr) / (343 + 0)

vr = 12.3

The speed of the car is 12.3 m/s.

You might be interested in

_____ motion occurs when tectonic plates move apart from each other. A. Divergent B. Transform C. Convergent

Likurg_2 [28]

A. Divergent (pretty sure)

4 0

4 years ago

Read 2 more answers

A swimming pool is circular with a 30-ft diameter. The depth is constant along east-west lines and increases linearly from 5 ft

Schach [20]

Answer : The volume of water in the pool is, 2473 ft³

Explanation :

First we have to calculate the average depth.

Given:

Diameter = 30 ft

Depth range : 1 to 6 ft linearly

average depth =

Now we have to calculate the volume of water in the pool.

Volume = area × average depth

V = π × (radius)² × 3.5

V = π × (30/2)² × 3.5

V = π × (15)² × 3.5

V = π × 225 × 3.5

V = 3.14 × 225 × 3.5

V = 2472.75 ft³ ≈ 2473 ft³

Therefore, the volume of water in the pool is, 2473 ft³

3 0

4 years ago

Read 2 more answers

During the first 5 seconds after a ball is dropped from rest, how far will it fall?

agasfer [191]

The answer is 125metre

5 0

3 years ago

A 2,200 kg railway freight car coasts at 3.6 m/s underneath a grain terminal, which dumps grain directly down into the freight c

suter [353]

Answer:

$m_2=2554.83\ kg$

Explanation:

Given that,

Mass of the car, $m_1=2200\ kg$

Initial speed of the car, $u=3.6\ m/s$

Final speed of the car, $v=3.1\ m/s$

To find,

The maximum mass of grain that it can accept.

Solution,

We know that according to the law of conservation of momentum, the initial momentum is equal to the final momentum.

$m_1u=m_2v$

$m_2=\dfrac{m_1u}{v}$

$m_2=\dfrac{2200\times 3.6}{3.1}$

$m_2=2554.83\ kg$

Therefore, the maximum mass of grain that it can accept is 2554.83 kg. Hence, this is the required solution.

7 0

3 years ago

What does Newton's second law describe?

Misha Larkins [42]

B. Newton's second law says that “when a constant force acts on a massive body, it causes it to accelerate, i.e., to change its velocity, at a constant rate.”

5 0

3 years ago