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
Yuki888 [10]
3 years ago
8

When an automobile moves with constant speed down a highway, most of the power developed by the engine is used to compensate for

the mechanical energy loss due to frictional forces exerted on the car by the air and the road. If the power developed by the engine is 168 hp, estimate the total friction force acting on the car when it is moving at a speed of 23 m/s. One horsepower equals 746 W.
Physics
1 answer:
uysha [10]3 years ago
7 0

Answer:

F=5449 N

Explanation:

Work done is a product of force and displacement ie

Work done, W, = Force*Displacement

Power, P, is Work done/Time

P=\frac {W}{t}=\frac {FS}{t} where P is power, W is work done, F is force, S is displacement and t is time

In this case, F is the frictional force. Converting the power from hp to W, we multiply by 746 hence P=746*168=125328  W

Since displacement/time is velocity, then

P=FV where V is velocity in m/s

Making F the subject

F=\frac {P}{V}

F=\frac {125328}{23}=5449.043478  N

F=5449 N

You might be interested in
In the past, how did people use the systematic movement of celestial bodies? Select all that apply.
vredina [299]
The answer is actually a,b, and d
Brainliest?
5 0
3 years ago
Read 2 more answers
Problem 1: Two sources emit waves that are coherent, in phase, and have wavelengths of 26.0 m. Do the waves interfere constructi
Anton [14]

1) Destructive interference

The condition for constructive interference to occur is:

\delta = m\lambda (1)

where

\delta =|d_1 -d_2| is the path difference, with

d_1 is the distance of the point from the first source

d_2 is the distance of the point from the second source

m is an integer number

\lambda is the wavelength

In this problem, we have

d_1 = 78.0 m\\d_2 = 143 m\\\lambda=26.0 m

So let's use eq.(1) to see if the resulting m is an integer

\delta =|78.0 m-143 m|=65 m\\m=\frac{\delta }{\lambda}=\frac{65 m}{26.0 m}=2.5

It is not an integer so constructive interference does not occur.

Let's now analyze the condition for destructive interference:

\delta = (m+\frac{1}{2})\lambda (2)

If we apply the same procedure to eq.(2), we find

m=\frac{\delta}{\lambda}-\frac{1}{2}=\frac{65.0 m}{26.0 m}-0.5=2

which is an integer: so, this point is a point of destructive interference.

2) Constructive interference

In this case we have

d_1 = 91.0 m\\d_2 =221.0 m

So the path difference is

\delta =|91.0 m-221.0 m|=130.0 m

Using the condition for constructive interference:

m=\frac{\delta }{\lambda}=\frac{130.0 m}{26.0 m}=5

Which is an integer, so this is a point of constructive interference.

3) Destructive interference

In this case we have

d_1 = 44.0 m\\d_2 =135.0 m

So the path difference is

\delta =|44.0 m-135.0 m|=91.0 m

Using the condition for constructive interference:

m=\frac{\delta }{\lambda}=\frac{91.0 m}{26.0 m}=3.5

This is not an integer, so this is not a point of constructive interference.

So let's use now the condition for destructive interference:

m=\frac{\delta}{\lambda}-\frac{1}{2}=\frac{91.0 m}{26.0 m}-0.5=3

which is an integer: so, this point is a point of destructive interference.

3 0
3 years ago
A python can detect thermal radiation from objects that differ in temperature from their environment as long as the received int
yanalaym [24]

Answer:

10.52 m

Explanation:

The power radiated by a body is given by

P = σεAT⁴ where ε = emissivity = 0.97, T = temperature = 30 C + 273 = 303 K, A = surface area of human body = 1.8 m², σ = 5.67 × 10⁻⁴ W/m²K⁴

P = σεAT⁴ = 5.67 × 10⁻⁸ W/m²K⁴ ×  0.97 × 1.8 m² × (303)⁴ = 834.45 W

This is the power radiated by the human body.

The intensity I = P/A where A = 4πr² where r = distance from human body.

I = P/4πr²

r = (√P/πI)/2

If the python is able to detect an intensity of 0.60 W/m², with a power of 834.45 W emitted by the human body, the maximum distance r, is thus

r = (√P/πI)/2 = (√834.45/0.60π)/2 = 21.04/2 = 10.52 m

So, the maximum distance at which a python could detect your presence is 10.52 m.

3 0
3 years ago
What tells you the strength of a wave?​
castortr0y [4]
The first factor is wind speed, the second factor is wind duration, and the last factor is the fetch, the distance over which the wind blows without a change in direction.

all these factors determines the strength of a wave.

hope this helps :)
3 0
3 years ago
As air pressure decreases, what happens
Naya [18.7K]

Answer:

I believe it is B, not 100% sure though

Explanation:

5 0
2 years ago
Other questions:
  • The same force is applied to two skateboards. One rolls across the room and the other moves a few feet and comes to a stop. Wher
    10·2 answers
  • What are the main causes of crack growth in rocks overtime
    12·2 answers
  • 50POINTS! What is the escape velocity for lunar module? Lunar module mass 15,200 kg radius of moon 1.74x106m, mass of moon 7.34x
    8·2 answers
  • A naughty squirrel jumps from a tree limb onto a birdfeeder. The tree limb is 4.5 m above the ground and the top of the birdfeed
    7·1 answer
  • A 1000 kg weather rocket is launched straight up. the rocket motor provides a constant acceleration for 16 s, then the motor sto
    9·1 answer
  • What is the Coriolis effect and doppler effect in detail. Tell me about both. Will give brainliest and lots of points
    5·1 answer
  • The ability of atoms to attract electrons is referred to as
    14·2 answers
  • At exactly the same time, Daisy and Damond both step off a diving platform 5 meters high. Damond jumps up and out from the platf
    11·1 answer
  • What is the Hairdryer energy transfers
    13·1 answer
  • Common sports injury : ankle sprain , bone fracture , muscle strain , neck low back pain , shoulder pain. First aid needed
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!