Can someone please help me ASAP???!!!

An observer is approaching at stationary source at 17.0 m/s. Assuming the speed of sound is 343 m/s, what is the frequency heard

UNO [17]

Answer:

the frequency heard by the observer is equal to 2677 Hz

Explanation:

given,

velocity of the observer = 17 m/s

speed of the sound = 343 m/s

velocity of the source = 0 m/s

frequency emitted from the source = 2550 Hz

$f = f_0(\dfrac{v-v_0}{v-v_s})$

$f = 2550\times (\dfrac{343+17}{343-0})$

velocity of observer is negative as it is approaching the source. f = 2676.38 Hz ≈ 2677 Hz

hence, the frequency heard by the observer is equal to 2677 Hz

7 0

3 years ago

B. What information did Wegener not have that would have strengthened his argument? (3

VMariaS [17]

<h2>Movement of Continents</h2>

Explanation:

Alfred Wegener was a German astronomer who proposed the "continental drift" hypothesis in 1910.
Alfred Wegener was not able to explain the movements of the continent in how and in which way they are moved.
He failed in an attempt to explain with the use of tides made the theory undefinable fully.
Also, the major problem with Wegener's theory of Continental Drift was that there was no proper explanation of a mechanism.

4 0

2 years ago

PHYSICS 50 POINTS PLEASE HELP

tangare [24]

Answer:

One way to look at Newton’s three laws of motion is this:

The third law states what forces are. That is, all forces are interactions between two different objects. If one object is interacting with another, then equal and opposite forces act on each object. So no force acts alone. When you exert a force on something, it is exerting the identical force back on you.

The first and second laws deal with the consequences of the forces that act on an object. The first law says that in the absence of a net force on an object, it simply continues doing whatever it was already doing. If it is at rest, it will remain at rest. If it is in motion, it will continue with that same motion - at constant speed and in the direction it was already traveling.

The second law says what happens if there is a net force on the object. In that case, the object accelerates - either by changing its speed, its direction, or both - in proportion and in the direction of the net force that acts on it. The amount of acceleration depends the object’s mass. That is, the larger the mass the smaller the acceleration for a given net force. The first and second laws can be summarized in the mathematical expression

F = ma

where F is the vector sum of all the forces that act on the object at any given moment (i.e., the net force), m is the mass of the object, and a is the acceleration of the object due to the net force at that moment - and is always in the same direction of the net force.

And notice that in a way, the first law is then “contained” within the second. That is, if the net force is zero on an object, then so is the acceleration. That is, either the object is (still) at rest or, if already in motion, the velocity didn’t change, in either case, the acceleration was zero.

Explanation:

4 0

2 years ago

Read 2 more answers

14. Saeed is pulling a 6 kg heavy rock with an upward force of 40 N but does not succeed to lift it up. What is the magnitude of

NemiM [27]

Answer:

58.8 N

Explanation:

The normal force is calculated as equal to the perpendicular component of the gravitational force.

Thus; N = mg

We are given m = 6 kg

Thus;

N = 6 × 9.8

N = 58.8 N

Thus, magnitude of normal force on the rock = 58.8 N

6 0

2 years ago

Three cars (car F, car G, and car H) are moving with the same speed and slam on their brakes. The most massive car is car F, and

Crazy boy [7]

To solve this problem it is necessary to apply the concepts related to Normal Force, frictional force, kinematic equations of motion and Newton's second law.

From the kinematic equations of motion we know that the relationship of acceleration, velocity and distance is given by

$v_f^2=v_i^2+2ax$

Where,

$v_f =$ Final velocity

$v_i =$ Initial Velocity

a = Acceleration

x = Displacement

Acceleration can be expressed in terms of the drag coefficient by means of

$F_f = \mu_k (mg) \rightarrow$ Frictional Force

$F = ma \rightarrow$ Force by Newton's second Law

Where,

m = mass

a= acceleration

$\mu_k =$ Kinetic frictional coefficient

g = Gravity

Equating both equation we have that

$F_f = F$

$\mu_k mg=ma$

$a = \mu_k g$

Therefore,

$v_f^2=v_i^2+2ax$

$0=v_i^2+2(\mu_k g)x$

Re-arrange to find x,

$x = \frac{v_i^2}{2(-\mu_k g)}$

The distance traveled by the car depends on the coefficient of kinetic friction, acceleration due to gravity and initial velocity, therefore the three cars will stop at the same distance.

3 0

2 years ago