Which phase must the moon be in during a solar eclipse?

What is the speed of a wave with a wavelength of 2 m and a frequency of 9 Hz?

ale4655 [162]

Answer:

The speed of a wave would be 18 with a wavelength of 2 m and a frequency of 9 Hz.

7 0

3 years ago

Please Help!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

arsen [322]

Answer:

Given that

speed u=4*10^6 m/s

electric field E=4*10^3 N/c

distance b/w the plates d=2 cm

basing on the concept of the electrostatices

now we find the acceleration b/w the plates to find the horizontal distance traveled by the electron when it hits the plate.

acceleration a=qE/m= $1.6*10^{-19}*4*10^3/9.1*10^{-31} =0.7*10^{15}$ = $7*10^{14}$ m/s

now we find the horizontal distance traveled by electrons hit the plates

horizontal distance

$X=u[2y/a]^{1/2}$

= $4*10^6[2*2*10^{-2}/7*10^{14}]^{1/2}$

= $3*10^{-2}$ = 3 cm

5 0

4 years ago

A car went 60 km in 5/6 of an hour while a second car went 54 km in 2/3h. Which car was faster? How many times faster?

Nastasia [14]

Answer:

The car that went 54 km in 2/3h was faster, 5/4 times faster than the other car

Explanation:

Average speed of a car is the ratio between the displacement $\Delta x$ and the time (t) it takes to do that displacement:

$V_{avg}=\frac{\Delta x}{t}$

So, for the first car:

$V_{avg1}=\frac{60km}{\frac{5h}{6}} =72\frac{km}{h}$ (1)

for the second car we have:

$V_{avg2}=\frac{60km}{\frac{2h}{3}} =90\frac{km}{h}$ (2)

So, the second cart is faster than the first one. To find how many times divide speed 2 by speed 1:

$\frac{90}{72}=\frac{5}{4}$

4 0

3 years ago

Bus starts from rest if the acceleration of the bus is 0.5 MS square what will be the velocity at the end of two minutes and wha

beks73 [17]

Answer:

1. 60 m/s.

2. 3600 m.

Explanation:

The following data were obtained from the question:

Initial velocity (u) = 0

Acceleration (a) = 0.5 m/s²

Time (t) = 2 mins

Final Velocity (v) =?

Distance travelled (s) =?

1. Determination of the velocity at the end of 2 minutes.

Initial velocity (u) = 0

Acceleration (a) = 0.5 m/s²

Time (t) = 2 mins = 2 x 60 = 120 secs

Final Velocity (v) =?

v = u + at

v = 0 + (0.5 x 120)

v = 60 m/s

Therefore, the velocity at the end of 2 minutes is 60 m/s.

2. Determination of the distance travelled.

Initial velocity (u) = 0

Acceleration (a) = 0.5 m/s²

Final velocity (v) = 60 m/s

Distance travelled (s) =..?

v² = u² + 2as

60² = 0 + 2 x 0.5 x s

3600 = 1 x s

s = 3600 m

Therefore, the distance travelled is 3600 m.

6 0

3 years ago

A household has a three-month electricity bill of $425. If the average unit cost of electricity is 8.5c, find:

Hunter-Best [27]

OK. We can do this.

3 months = 90 days

The unit cost is ($0.085) per kilowatt-hour

Here we go:

($ 425/90da) · (1da/24hr) · (1 da/86,400sec) · (1 kW-hr/$ 0.085) =

(425 · 1 · 1 · 1) / (90 · 24 · 86,400 · 0.085) · ($-da-da-kW-hr / da-hr-sec-$) =

2.679 x 10⁻⁵ day-kW/sec

This is not too useful yet. It needs some more unit conversion.

I think all it needs is another (1 day = 86,400 sec) .

(2.679 x 10⁻⁵ day-kW/sec) · (86,400 sec / da) =

(2.679 x 10⁻⁵ · 86,400) · (da-kW-sec / sec-da) =

2.315 kW

If I have not gang aglay somewhere in all of that, then this is the answer to the question: 2.315 kW .

I know that you probably didn't follow everything that I did, and if you did, you don't have a lot of confidence in this answer. I have to admit that I have serious doubts too. So I have to check the answer somehow.

What would it cost if the household was using power steadily at the rate of 2.315 kilowatts, and the family went away for three months and just left everything cooking like that ?

2.315 kilowatts ===> 2.315 kilowatt-hours every hour

(2.315 kW hours per hr) x (24 hrs per day) = 55.56 kWh per day

(55.56 kWh per day) x (90 days) = 5,000.4 kWh

(5,000.4 kWh) x (8.5¢ for each kWh) = 42,503.4¢ on the bill

42,503.4¢ = $425.034 That's good enough for me ! ! I rest my case.

5 0

3 years ago