In the rectangle to the left, if

A driver in a 2000 kg Porsche wishes to pass to pass a slow-moving school bus on a four-lane road. What is the average power in

creativ13 [48]

Answer:

The power require to accelerate the car is, P = 299700 watts

Explanation:

Give data,

The mass of the car, m = 2000 kg

The initial velocity of the sports car, u = 30 m/s

The final velocity of the sports car, v = 60 m/s

The time period of acceleration, t = 9 s

The acceleration of the car, a = (v-u) / t

= (60 - 30) / 9

= 3.33 m/s²

The displacement of the car,

S = ut + ½ at²

= 30 x 9 + ½ x 3.33 x 9²

= 405 m

The force acting on the car, F = m x a

= 2000 x 3.33

= 6660 N

The work done by the car, W = F S

= 6660 x 405

= 2697300 J

The power of the car, P = W / t

= 2697300 / 9

= 299700 watts

Hence, the power require to accelerate the car is, P = 299700 watts

4 0

4 years ago

You need to design a photodetector that can respond to the entire range of visible light. True or False

Rasek [7]

Answer: True

Explanation:

A photo detector that can respond to the entire rang of visible light can be design, it is true.

Photo detector is a device in an optical receiver which receives optical signals and convert it to electric signal. It is the key device position in front of the optical receiver.

7 0

3 years ago

58

Basile [38]

Answer:

T = 0.01 s

Explanation:

Given that,

The frequency of the beats of a hummingbird, f = 100 Hz

We need to find the period of the hummingbirds flaps. Let the time is t. We know that the relation between frequency and time period is given by :

T = 1/f

Put all the values,

T = 1/100 = 0.01 s

So, the time period of the humming bird is 0.01 s.

3 0

3 years ago

A motorist drives north for 35.0 minutes at 85.0 kph. He then stops for 15.0 minutes. The motorist then drives 130.0 km in 2.0 h

o-na [289]

Answer:

A. 216.36 $\frac{km}{h}$

B. 96.56 $\frac{km}{h}$

Explanation:

Let $s_{1}$ be the distance in first part.

$s_{1}$ = velocity × time

$s_{1}$ = 85 × $\frac{35}{60}$

$s_{1}$ = 49.58 km

Let $s_{2}$ be the distance in first part.

$s_{2}$ = 130 km

Average velocity = $\frac{Total displacement}{Total time}$

When second leg of the trip is

A. Toward north

Average velocity = $\frac{[tex] s_{1} + s_{2}$ }{Total time} [/tex]

Average velocity = $\frac{130+49.58}{0.25+0.58}$

Average velocity =216.36 $\frac{km}{h}$

B. Toward south

Average velocity = $\frac{[tex] s_{1} - s_{2}$ }{Total time} [/tex]

Average velocity = $\frac{130-49.58}{0.25+0.58}$

Average velocity =96.56 $\frac{km}{h}$

3 0

3 years ago

Which of the following statements are true?

Tems11 [23]

Answer:

1) A time-varying magnetic field will produce an electric field.

4) A time-varying electric field will produce a magnetic field.

Explanation:

1) A time-varying magnetic field will produce an electric field.

TRUE

time varying magnetic field will produce electric field which is given as

$E = \frac{r}{2}\frac{dB}{dt}$

2) Time-varying electric and magnetic fields can propagate through space only if there is no matter in their path.

FALSE

Time varying electric field and magnetic field will induce each other and it can travel through any medium as well as it can travel without any medium also

3) Electric and magnetic fields can be treated independently only if they vary in time.

FALSE

electric field can be due to stationary charge and magnetic field due to current carrying elements so it is not compulsory to have time varying

4) A time-varying electric field will produce a magnetic field.

TRUE

Time varying electric field will produce magnetic field given as

$B = \frac{\mu_o\epsilon_o A}{2r}\frac{dE}{dt}$

3 0

3 years ago