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
Novosadov [1.4K]
3 years ago
11

. (a) How high a hill can a car coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110

km/h? (b) If, in actuality, a 750-kg car with an initial speed of 110 km/h is observed to coast up a hill to a height 22.0 m above its starting point, how much thermal energy was generated by friction? (c) What is the average force of friction if the hill has a slope 2.5º above the horizontal?
Physics
1 answer:
7nadin3 [17]3 years ago
8 0

Answer:

(a) the high of a hill that car can coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h is 47.6 m

(b) thermal energy was generated by friction is 1.88 x 10^{5} J

(C) the average force of friction if the hill has a slope 2.5º above the horizontal is 373 N

Explanation:

given information:

m = 750 kg

initial velocity, v_{0} = 110 km/h = 110 x 1000/3600 = 30.6 m/s\frac{30.6^{2} }{2x9.8}

initial height, h_{0} = 22 m

slope, θ = 2.5°

(a) How high a hill can a car coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h?

according to conservation-energy

EP = EK

mgh = \frac{1}{2} mv_{0} ^{2}

gh = \frac{1}{2} v_{0} ^{2}

h = \frac{v_{0} ^{2} }{2g}

  = 47.6 m

(b) If, in actuality, a 750-kg car with an initial speed of 110 km/h is observed to coast up a hill to a height 22.0 m above its starting point, how much thermal energy was generated by friction?

thermal energy = mgΔh

                         = mg (h - h_{0})

                         = 750 x 9.8 x (47.6 - 22)

                         = 188160 Joule

                         = 1.88 x 10^{5} J

(c) What is the average force of friction if the hill has a slope 2.5º above the horizontal?

f d  = mgΔh

f = mgΔh / d,

where h = d sin θ, d = h/sinθ

therefore

f = (mgΔh) / (h/sinθ)

 = 1.88 x 10^{5}/(22/sin 2.5°)

 = 373 N

You might be interested in
Define Plateau period.
Amiraneli [1.4K]
A plateau period refers to a period in life where you are kind of stuck in the middle. There is little growth or decline so you are kind of at a standstill.

please vote my answer brainliest. thanks!
5 0
3 years ago
Which best describes how energy changes form in a car's engine?
andrezito [222]

Answer:

Multiple transformations occur because the chemical energy of the fuel is changed to several forms of energy

Explanation:

In a car engine, multiple energy transformation takes place. The chemical energy storef in fuel is transformed into mechanical energy which helps move the wheels of the vehicle.

The mechanical energy can also be transformed into electrical energy through a sort of dynamo system in vehicles. Stereo players use the electrical energy to produce sound.

We see that multiple energy conversions are common in a motor car.

6 0
3 years ago
Read 2 more answers
Consider a projectile launched with an initial velocity of v0 = 120 ft/s, inclined at an angle, θ with the horizontal. Let us as
Natali [406]

Answer:

How to find the maximum height of a projectile?

if α = 90°, then the formula simplifies to: hmax = h + V₀² / (2 * g) and the time of flight is the longest. ...

if α = 45°, then the equation may be written as: ...

if α = 0°, then vertical velocity is equal to 0 (Vy = 0), and that's the case of horizontal projectile motion.

Explanation:

4 0
3 years ago
Determine qual é a carga elétrica de um corpo que possui 1 milhão de partículas?
MaRussiya [10]

Answer:

This can be translated to:

"find the electrical charge of a body that has 1 million of particles".

First, it will depend on the charge of the particles.

If all the particles have 1 electron more than protons, we will have that the charge of each particle is q = -e = -1.6*10^-19 C

Then the total charge of the body will be:

Q = 1,000,000*-1.6*10^-19 C = -1.6*10^-13 C

If we have the inverse case, where we in each particle we have one more proton than the number of electrons, the total charge will be the opposite of the one of before (because the charge of a proton is equal in magnitude but different in sign than the charge of an electron)

Q = 1.6*10^-13 C

But commonly, we will have a spectrum with the particles, where some of them have a positive charge and some of them will have a negative charge, so we will have a probability of charge that is peaked at Q = 0, this means that, in average, the charge of the particles is canceled by the interaction between them.

7 0
3 years ago
A projectile is launched with an initial speed of 60.0 m/s at an angle of 30.0° above the horizontal. The projectile lands on a
vodka [1.7K]

Answer:

51.96 m/s^-1

Explanation:

a) see the attachment

b) As we know the velocity of the projectile has two component, horizontal velocity v_ox. and vertical velocity v_oy as shown in the figure. At the highest point of the trajectory, the projectile has only horizontal velocity and vertical velocity is zero. Therefore at the highest point of the trajectory, the velocity of the projectile will be  

v_ox=v_o*cosФ

       =60*cos (30)

      = 51.96 m/s^-1

3 0
3 years ago
Read 2 more answers
Other questions:
  • Because it implies royal status, the granary at the Conical tower and circular wall of Great Zimbabwe is most similar to what ob
    13·1 answer
  • Why do heavier people have a lower blood and alcohol level?
    13·1 answer
  • 17. What are the two factors that can cause the volume of water in the ocean to change? A. Temperature and pressure B. Gravity a
    15·1 answer
  • The deflection of prevailing winds and ocean currents in the northern hemisphere is called
    8·1 answer
  • Two students, sitting on frictionless carts, push against each other. Both are initially at rest and the mass of student 1 and t
    8·1 answer
  • If a charge travels through a magnetic field, it experiences a magnetic force and its velocity is perpendicular to the direction
    12·1 answer
  • Which of the following would NOT be considered vigorous aerobic exercise?
    5·2 answers
  • Imagine you have a collection of identical flat-bottomed coffee filters that can be nested (stacked inside of each other) so tha
    13·1 answer
  • A motorcycle is traveling along a highway at 29 m/s. How far does the motorcycle travel in 18 s?
    13·1 answer
  • How net current on a toroid is zero?​
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!