1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
yawa3891 [41]
3 years ago
7

A searchlight is 210 ft from a straight wall. As the beam moves along the​ wall, the angle between the beam and the perpendicula

r to the wall is increasing at the rate of 2.0 degrees divided by s. How fast is the length of the beam increasing when it is 290 ft​ long?

Physics
1 answer:
Ivenika [448]3 years ago
4 0

Answer:

The length of the beam increasing is 9.64 ft/s.

Explanation:

Given that,

Height = 210 ft

Distance =290 ft

According to figure,

We need to calculate the angle

\cos\theta=\dfrac{210}{x}....(I)

Put the value of x in the equation

\cos\theta=\dfrac{210}{290}

\cos\theta=\dfrac{21}{29}=0.72

Now, \sin\theta=\dfrac{20}{29}

On differentiate of equation (I)

-\sin\theta\dfrac{d\theta}{dt}=-\dfrac{-210}{x^2}\dfrac{dx}{dt}

\sin\theta=\dfrac{210}{x^2}\dfrac{dx}{dt}

Put the value in the equation

\sin\dfrac{20}{29}\times2.0=\dfrac{210}{(290)^2}\dfrac{dx}{dt}

\dfrac{dx}{dt}=\sin\dfrac{20}{29}\times2.0\times\dfrac{290^2}{210}

\dfrac{dx}{dt}=9.64\ ft/s

Hence, The length of the beam increasing is 9.64 ft/s.

You might be interested in
What is surface tension??​
Nadya [2.5K]

Answer:

<h2>internal force per unit area on a solid or liquid surface is called surface tension...</h2>
6 0
3 years ago
How can wasted energy be made useful?
murzikaleks [220]

Answer:

by using it in a such place or thing which needs it or which can work with it

7 0
2 years ago
The Lamborghini Huracan has an initial acceleration of 0.75g. Its mass, with a driver, is 1510 kg.
Cerrena [4.2K]

Answer:

11109.825 N

Explanation:

Given Data:

total mass =m=1510 kg

initial acceleration (a) =0.75g                  ( g=9.81 m/s² )

F=ma

  = (1510)*( 0.75*9.81)

  = 11109.825 N

4 0
3 years ago
What type of power plant burns material to make electricity?
Alecsey [184]
<h2>Hello!</h2>

The answer is: D. Coal

<h2>Why?</h2>

Coal power plants burn coal in to get steam, the steam flows into a turbine which is coupled to an electrical generator.

Coal power plants work burning high amounts of coal into a boiler, generation a lot of steam under extreme pressures. The steam is obtained when the water is heated by the burning coal, then the steam is cooled, being transformed in liquid water again (due the condensation process) and it's sent back on a cyclical process.

Have a nice day!

6 0
3 years ago
Read 2 more answers
Calculate (a) the torque, (b) the energy, and (c) the average power required to accelerate Earth in 4.0 days from rest to its pr
natima [27]
<h2>Answer:</h2>

Torque = <em>2.05 x 10²⁸ Nm</em>

Energy = <em>3.54 x 10³³ J</em>

Average power = <em>1.02 x 10²⁸ W</em>

<h2>Explanation:</h2>

(a) Torque (τ) is the rotational effect of a given force.  

It is given by

τ = I x α          -------------(i)

Where;

I = rotational inertia of the object

α = angular acceleration of the object.

In this case, the object is the Earth. Therefore,

I = 9.71 x 10³⁷ kg m²

α = ω / t

Where;

ω = angular velocity of earth = 2π rad / day

<em>Since </em>

<em>1 day = 24 hours and 1 hour = 3600seconds</em>

<em>1 day = 24 x 3600 seconds = 86400seconds</em>

<em>=> ω = 2π rad / 86400seconds</em>

<em>=> ω = 7.29 × 10⁻⁵ rad/s</em>

<em />

t = 4 days = 4 x 24 x 3600 seconds = 345600 seconds

=> α = ω / t

=> α = 7.29 × 10⁻⁵ / 345600

=> α = (7.29 × 10⁻⁵) / (3.456 x 10⁵)

=> α = (7.29 × 10⁻⁵⁻⁵) / (3.456)

=> α = (7.29 × 10⁻¹⁰) / (3.456)

=> α = 2.11 × 10⁻¹⁰ rad/s²

Now substitute the values of I and α into equation (i)

τ = 9.71 x 10³⁷ x 2.11 × 10⁻¹⁰

τ = 9.71 x 10²⁷ x 2.11

τ = 20.5 x 10²⁷ Nm

τ = 2.05 x 10²⁸ Nm

(ii) The energy (rotational energy) E is given by;

E = \frac{1}{2} x I x ω

E = \frac{1}{2} x 9.71 x 10³⁷ x 7.29 × 10⁻⁵

E = 35.4 x 10³² J

E = 3.54 x 10³³ J

(iii) The average power P, is given by;

P = E / t

P = 3.54 x 10³³ / 345600

P = 1.02 x 10²⁸ W

5 0
3 years ago
Other questions:
  • What is a unit of mass?
    14·1 answer
  • One of the main arguments that animal rights advocates present is that animals have rights because they __________.
    9·2 answers
  • What does the force of gravity between two objects depend on?
    12·1 answer
  • Distinguish between the positive and negative influences scientific knowledge can have on society
    13·2 answers
  • What forms when two continental plates collide?
    12·1 answer
  • A 1.20 m wire has a mass of 6.80 g and is under a tension of 120 N. The wire is held rigidly at both ends and set into oscillati
    9·1 answer
  • A block is released from the top of a frictionless incline plane as pictured above. If the total distance travelled by the block
    13·1 answer
  • el of a Shs when places in water. The same piece of day ficas ftis made into the stage of a boat. Why does the day ficat when ma
    12·1 answer
  • Examples of impact printers​
    6·1 answer
  • A ball is thrown vertically upward. As it rises, what happens to its total energy?.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!