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.
Answer:
The initial acceleration of the 59g particle is 
Explanation:
Newton's second laws relates acceleration (a), net force(F) and mass (m) in the next way:
(1)
We already know the mass of the particle so we should find the electric force on it to use on (1), the magnitude of the electric force between two charged objects by Columb's law is:
with q1 and q2 the charge of the particles, r the distance between them and k the constant 
. So:
Using that value on (1) and solving for a
Responder:
<h2>
490 julios
</h2>
Explicación:
Se dice que el trabajo se realiza cuando una fuerza aplicada a un objeto hace que el objeto se mueva a través de una distancia. El trabajo realizado por un cuerpo se expresa mediante la fórmula;
Workdone = Fuerza * Distancia
Como Fuerza = masa * aceleración,
Workdone = masa * aceleración * distancia
Masa dada = 5.0kg, aceleración = 2.0m / s² d =?
Para obtener d, usaremos una de las leyes del movimiento,
d = ut + 1 / 2at²
u = 0 (ya que el cuerpo acelera desde el reposo) yt = 7.0s
d = 0 + 1/2 (2) (7) ²
d = 49m
Workdone = 5 * 2 * 49
Workdone = 490 Julios
<u>Answer:</u>
Prior to exercise, a proper warm-up of 10-15 minutes is extremely important to avoid injuries.
- Don't go too hard in the beginning and boost your activity level slowly. A good indication of a proper warm-up is that you feel sweat on your body parts.
- Don't overstretch right in the beginning as it can cause sore in your muscles and joints or stress fractures.
- Take a break if you feel sick or fatigues and use other drinks along with water to replace electrolytes and body fluids.
