Ask question

Ask question

All categories

2 years ago

8

15 beats are heard in 5 seconds when a piano key and a tuning fork of slightly higher frequency (440 Hz) are struck at the same

time. What is the frequency of the sound emitted by the piano key?

1 answer:

chubhunter [2.5K]2 years ago

6 0

Answer:

437Hz

Explanation:

if two sound waves have a little difference in frequencies $f_{a}$ and $f_{a}$ interfere, the resulting sound wave produces a beat.

Given:

$f_{a}=440Hz$

$f_{b}=frequency\ of\ the\ sound\ emitted by\ the\ piano\ key$

$f_{beat}=frequency\ of\ beat$

where

$f_{beat}=\frac{number\ of\ beat}{time}$

$f_{beat}=\frac{15beats}{5}=3Hz$

$f_{beat}=f_{a}-f_{b}$

$f_{b}=f_{a}-f_{beat}$ = 440Hz - 3Hz = 437Hz

You might be interested in

A bus is moving in astraight line at speed of 25m/s. What time does bus take to cover 5 km

WARRIOR [948]

Answer:

Kinematics

given,

time (t)=100 s, distance (s)=1 km=1000 m

V

b

=10m/s (relative speed r.p to bus)

Velocity (v)=

time

distance

=

100

1000

V

s

= velocity of scooter

V

b

→ Velocity of bus

V=V

s

−V

b

→As we know

10=V

s

−10

20=V

s

V

s

=20 m/s

Velocity with which scooterist

should chase the bus →20 m/s

Explanation:

I Hope you Guys Understood

please mark as Brainliest....

5 0

2 years ago

Legacy issues $570,000 of 8.5%, four-year bonds dated January 1, 2019, that pay interest semiannually on June 30 and December 31

choli [55]

Answer:

1) Determine the total bond interest expense to be recognized.

Total bond interest expense over life of bonds:

Amount repaid:

8 payments of $24,225: $193,800

Par value at maturity: $570,000

Total repaid: $763800 (193,800 + 570,000)

Less amount borrowed: $508050

Total bond interest expense: $255750 (763800 - 508,050)

2)Prepare a straight-line amortization table for the bonds' first two years.

Semiannual Interest Period End; Unamortized Discount; Carrying Value

01/01/2019 61,950 508,050

06/30/2019 54,206 515,794

12/31/2019 46,462 523,538

06/30/2020 38,718 531,282

12/31/2020 30,974 539,026

3) Record the interest payment and amortization on June 30:

June 30 Bond interest expense, dr 31969

Discount on bonds payable, Cr (61950/8) 7743.75

Cash, Cr ( 570000*8.5%/2) 24225

4) Record the interest payment and amortization on December 31:

Dec 31 Bond interest expense, Dr 31969

Discount on bonds payable, Cr 7744

Cash, Cr 24225

6 0

3 years ago

Why does a bouncing ball rise to a lower height with each bounce?

grandymaker [24]

Because after each impact it loses a fraction of its original energy, because it gets transfered to the floor. this is the reason that a perpetual motion machine is impossible. you cannot have infinite energy, because to perform a task, energy must be spent. hope i helped :3

7 0

3 years ago

To practice Problem-Solving Strategy 8.1 for circular-motion problems. A cyclist competes in a one-lap race around a flat, circu

Anna007 [38]

Answer:

Explanation:

distance travelled

s = 2πR

= 2 X 3.14 X 140

= 880 m

final velocity = v

initial velocity = u

distance travelled = s

time = 60 s

s = ut + 1/2 at²

880 = .5 x a x 60²

a = .244 m/s²

final velocity v = at

= .244 x 60

= 14.66

centripetal acceleration at final moment

v² /R

14.66 X 14.66 / 140

= 1.53 m/s⁻²

1.53 m/s²

this is centripetal acceleration which acts towards the centre.

tangential acceleration calculated a _t = .244

redial acceleration ( centripetal ) = 1.53

Resultant acceleration

R²= 1.53² + .244 ²

R = 1.55 m/s²

total force = 1.55 x 76

= 118 N

5 0

2 years ago

Jeff of the Jungle swings on a 7.6-m vine that initially makes an angle of 32 ∘ with the vertical.

shtirl [24]

To solve this problem we will use the trigonometric concepts to find the distance h, which will allow us to find the speed of Jeff and that will finally be the variable that will indicate the total tension, since it is the variable of the centrifugal Force given in the vine at the lowest poing of the swing.

From the image:

$cos (32) = \frac{(7.6-h)}{7.6}$

$h = 1.1548m$

When Jeff reaches his lowest point his potential energy is converted to kinetic energy

$PE = KE$

$mgh = \frac{1}{2} mv^2$

$v = \sqrt{2gh}$

$v = \sqrt{2(9.8)(1.1548)}$

$v= 4.75m/s$

Tension in the string at the lowest point is sum of weight of Jeff and the his centripetal force

$T = W+F_c$

$T = mg + \frac{mv^2}{r}$

$T = (83)(9.8)+\frac{(9.8)( 4.75)^2}{7.6}$

$T = 842.49N$

Therefore the tension in the vine at the lowest point of the swing is 842.49N

3 0

2 years ago