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
aivan3 [116]
2 years ago
13

A 350-kg roller coaster car starts from rest at point A and slides down a frictionless loop-the-loop (Pig. P7.41). (a) How fast

is this roller coaster car moving at point B? (b) How hard does it press against the track at point B?
Physics
2 answers:
Mrac [35]2 years ago
6 0

Answer:

(a)v2 = 16m/s at point B

(b) F = 1.49×10⁴N.

Explanation:

Given m = 350kg

At A, h = 25m

At B h = 12m

(a) We are required to calculate the speed at this point, B.

This problem involves the application of the concept of conservation of mechanical energy for its solution since gravity is the only force doing work on the system.

So for this system,

ΔKE = – ΔPE

1/2×m(v2²– v1²) =– mg(h2 – h1)

From the diagram, g

h2 = 12m, h1 = 25m. From the question it was stated that the car starts from rest so v1 = 0m/s

In the above equation m is common to both sides so they cancel out. So,

1/2×(v2²– 0²) = – g(12 – 25)

1/2v2² = 13g

V2² = 2 ×13g = 26×9.80

v2 ² = 254.8

v2 = √254.8 = 15.96m/s ≈ 16m/s.

Energy concepts have been used to solve this problem. In this approach only the start and end points are taking into consideration when doing analysis on any problem of this sort and not what happens in between.

(b) Ghis part is asking us to calculate the force at point B.

At point B the car is moving in a uniform circle of diameter 12m (radius 6m)

So the acceleration of the car at point B

a = v²/r

v = 16m/s, r = 6m

F = ma = m×v²/r = 350×16²/6 = 14933.33N

F = 1.49×10⁴N.

Leona [35]2 years ago
3 0

Answer:

a)Velocity of car =v=16 m/s

b)Force against the track at point B=1.15*10^{4}N

Explanation:

Given mass of roller coaster=m=350 kg

Position of A=Ha=25 m

Position of B=Hb=12 m

Net potential energy=mg(ha-hb)

Net potential energy=(350)(9.80)(25-12)

Net potential energy=44590 J

Using energy conservation

net kinetic energy=net potential energy

(1/2)mv^2=mg(ha-hb)

m=350

velocity=v=16 m/s

b)There two force acting,centripetal force upward and gravity downward.

Thus net force acting will be

Net force=(mv^2/r)-mg

Net force=14933.33-3430

Net force=1.15*10^{4} N

You might be interested in
Determine the specific heat of a certain metal if a 450 gram sample of it loses 34 500 Joules of heat as its temperature starts
slamgirl [31]

Answer:

c = 0.4356 J/gK

Explanation:

Given the following data;

Mass = 450 grams

Initial temperature, T1 = 150°C

Final temperature, T2 = 53°C

Quantity of heat = 34500 Joules

To find the specific heat capacity of the metal;

Heat capacity is given by the formula;

Q = mcdt

Where;

Q represents the heat capacity or quantity of heat.

m represents the mass of an object.

c represents the specific heat capacity of water.

dt represents the change in temperature.

dt = T2 - T1

dt = 53 - 150

dt = -97°C

Converting the temperature in Celsius to Kelvin, we have;

dt = 273 + (-97) = 176 Kelvin

Making c the subject of formula, we have;

c = \frac {Q}{mdt}

Substituting into the equation, we have;

c = \frac {34500}{450*176}

c = \frac {34500}{79200}

c = 0.4356 J/gK

6 0
2 years ago
An atomic nucleus is composed of
musickatia [10]

Answer:

84 protons and 128 neutron

8 0
2 years ago
A very elastic rubber ball is dropped from a certain height and hits the floor with a (2pts) downward speed v. Since it is so el
artcher [175]

Answer:

3.True. The magnitude of momentum is the same

Explanation:

Let's propose the solution of the problem

The initial moment is

                     p₀ = m v

The final moment

                     p_{f} = m (-v)

 

                  p₀ = - p_{f}

Now we can review the claims

1. False. We see that the moment module is the same, but its direction changes

2. False. The impulse is a vector

3.True. The magnitude of momentum is the same

7 0
3 years ago
You are given aqueous solutions of six different substances and asked to determine whether they are strong, weak, or nonelectrol
kogti [31]

Answer:

Answer is explained below;

Explanation:

Electrolytes are any substances that dissociate into charged particles called ions when dissolved in water. The positively charged ions called cations and the negatively charged ions called anions move toward the negative and positive terminals (cathode and anode) of an electric circuit.

When a substance dissolved in water completely dissociates into ions, it is called a strong electrolyte. The aqueous solutions containing strong electrolytes conduct electricity very well and the examples include strong acids and soluble ionic compounds such as barium chloride, sodium hydroxide, etc.  

When a substance dissolved in water does not completely dissociate into ions, it is called a weak electrolyte. Since the aqueous solutions containing weak electrolytes have relatively few ions, their electrical conductivity is very low compared to the solutions containing strong electrolytes. Examples of weak electrolytes include weak acids and bases like acetic acid, ammonia, etc.

When a substance does not dissociate into ions when dissolved in water, it is called a nonelectrolyte. Since the aqueous solutions containing nonelectrolytes do not contain any ions, such solutions do not conduct electricity. Examples of nonelectrolytes are ethanol, aldehydes, glucose, ketones, etc.

If a solution contains dissolved ions, it conducts electricity and as the ion concentration increases, the conductivity also increases. To determine whether the aqueous solutions of six different substances are strong, weak, or nonelectrolytes, we can test them by applying a voltage to electrodes immersed in the solutions and a light bulb. By observing the brightness of the light bulb or by measuring the flow of electrical current, we can find out which solution contains a strong electrolyte or weak electrolyte, or nonelectrolyte.

If the solution contains a nonelectrolyte, the current flow is nil and the light bulb does not glow. If the solution contains a strong electrolyte, the current flow is very strong and so the brightness of the light bulb is very high. If the solution contains a weak electrolyte, the current flow is much low compared to the strong electrolyte and the light bulb glows, but the brightness is very low.

3 0
3 years ago
Be sure to answer all parts. Assume the diameter of a neutral helium atom is 1.40 × 102 pm. Suppose that we could line up helium
ss7ja [257]

Answer:

The number of atoms are 1.86\times10^{8}.

Explanation:

Given that,

Diameter D = 1.40\times10^{2}\ pm

D=1.40\times10^{2}\times10^{-12}\ m

Distance = 2.60 cm

We calculate the number of atoms

Using formula of numbers of atoms

Number\ of\ atoms =\dfrac{2.60\times10^{-2}}{1.40\times10^{2}\times10^{-12}}

Number\of\atoms =1.86\times10^{8}

Hence, The number of atoms are 1.86\times10^{8}.

8 0
2 years ago
Other questions:
  • A. Two point charges totaling 7.50 µC exert a repulsive force of 0.100 N on one another when separated by 0.911 m. What is the c
    6·1 answer
  • The law of reflection states that the angle of reflection is equal to the angle of
    8·1 answer
  • Can an electron be found in an exact spot within an atom
    11·1 answer
  • A 1-m-tall barrel is closed on top except for a thin pipe extending 4.2 m up from the top. When the barrel is filled with water
    5·1 answer
  • Report this plssssssssss
    5·1 answer
  • Explain the process of photosynthesis, se sure to include the reactants and products.
    14·1 answer
  • I shoot a bullet up at 270 m/s. How long does it fly for????
    9·1 answer
  • What is used to calculate or determine intensity during exercise
    13·1 answer
  • A person might be using social media in an unhealthy way if:
    14·2 answers
  • I need help with the problem below
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!