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
Luda [366]
3 years ago
15

A 1500 kg car skids to a halt on a wet road where μk = 0.51. how fast was the car traveling if it leaves 66-m-long skid marks?

Physics
1 answer:
djverab [1.8K]3 years ago
3 0

We got coefficient of friction uk = 0.51<span>
Mass m = 1500 kg 
normal force on the car = weight of the car = 1500 * 9.8 N = 14700 N 
and the force of friction on the car, f = uk * normal force = 0.51 * 14700 N = 7497 N 
taking Acceleration a = -f/m = -7497/1500 = -4.998 m/s^2 
Displacement s = 66 m 
Final velocity v = 0 
Initial velocity u = ? 
v^2 = u^2 + 2as 
<span>0 = u^2 - 2 * 4.998 * 66
<span>u = 25.69 m/s </span></span></span>

You might be interested in
What are two ways electromagnetic waves are used in a home computer scanner?
miss Akunina [59]

Answer:

A and B

Explanation:

8 0
2 years ago
Read 2 more answers
a 4kg metal block absorbs 5000j of energy and increases to a temperature of 22°c. the metal has a specific heat capacity of 250j
e-lub [12.9K]

Answer:

17 °C

Explanation:

From specific Heat capacity.

Q = cm(t₂-t₁)................. Equation 1

Where Q = Heat absorb by the metal block, c = specific heat capacity of the metal block, m = mass of the metal block, t₂ = final temperature, t₁ = Initial temperature.

make t₁ the subject of the equation

t₁ = t₂-(Q/cm)............... Equation 2

Given: t₂ = 22 °C, Q = 5000 J, m = 4 kg, c = 250 J/kg.°c

Substitute into equation 2

t₁ = 22-[5000/(4×250)

t₁ = 22-(5000/1000)

t₁ = 22-5

t₁ = 17 °C

6 0
3 years ago
Calculate the wavelength of each frequency of electromagnetic radiation: a. 100.2 MHz (typical frequency for FM radio broadcasti
Natalka [10]

Answer:

a). 100.2 MHz (typical frequency for FM radio broadcasting)

The wavelength of a frequency of 100.2 Mhz is 2.99m.

b. 1070 kHz (typical frequency for AM radio broadcasting) (assume four significant figures)

The wavelength of a frequency of 1070 khz is 280.3 m.

c. 835.6 MHz (common frequency used for cell phone communication)

The wavelength of a frequency of 835.6 Mhz is 0.35m.

Explanation:

The wavelength can be determined by the following equation:

c = \lambda \cdot \nu  (1)

Where c is the speed of light, \lambda is the wavelength and \nu is the frequency.  

Notice that since it is electromagnetic radiation, equation 1 can be used. Remember that light propagates in the form of an electromagnetic wave.

<em>a). 100.2 MHz (typical frequency for FM radio broadcasting)</em>

Then, \lambda can be isolated from equation 1:

\lambda = \frac{c}{\nu} (2)

since the value of c is 3x10^{8}m/s. It is necessary to express the frequency in units of hertz.

\nu = 100.2 MHz . \frac{1x10^{6}Hz}{1MHz} ⇒ 100200000Hz

But 1Hz = s^{-1}

\nu = 100200000s^{-1}

Finally, equation 2 can be used:

\lambda = \frac{3x10^{8}m/s}{100200000s^{-1}}

\lambda = 2.99 m

Hence, the wavelength of a frequency of 100.2 Mhz is 2.99m.

<em>b. 1070 kHz (typical frequency for AM radio broadcasting) (assume four significant figures)</em>

<em> </em>

\nu = 1070kHz . \frac{1000Hz}{1kHz} ⇒ 1070000Hz

But  1Hz = s^{-1}

\nu = 1070000s^{-1}

Finally, equation 2 can be used:

\lambda = \frac{3x10^{8}m/s}{1070000s^{-1}}

\lambda = 280.3 m

Hence, the wavelength of a frequency of 1070 khz is 280.3 m.

<em>c. 835.6 MHz (common frequency used for cell phone communication) </em>

\nu = 835.6MHz . \frac{1x10^{6}Hz}{1MHz} ⇒ 835600000Hz

But  1Hz = s^{-1}

\nu = 835600000s^{-1}

Finally, equation 2 can be used:

\lambda = \frac{3x10^{8}m/s}{835600000s^{-1}}

\lambda = 0.35 m

Hence, the wavelength of a frequency of 835.6 Mhz is 0.35m.

6 0
3 years ago
A ball is projected vertically upward from the surface of the Earth with an initial speed of +49 meters per second. The ball rea
fenix001 [56]
Answer: 245 meters

Explanation: 49 ? Meters
over over over
1 5 seconds

Cross multiply- 49 times 5 divided by 1 which equals 245
8 0
3 years ago
Richard Julius once made a model plane that could travel a max speed of 110 m/s. Suppose the plane was held in a circular path b
hjlf

Answer:

85.8 m/s

Explanation:

We know that the length of the circular path, L the plane travels is

L = rθ where r = radius of path and θ = angle covered

Now,its speed , v = dL/dt = drθ/dt = rdθ/dt + θdr/dt

where dθ/dt = ω = angular speed = v'/r where v' = maximum speed of plane and r = radius of circular path

Now, from θ = θ₀ + ωt where θ₀ = 0 rad, ω = angular speed  and t = time,

θ = θ₀ + ωt = 0 + ωt = ωt

So, v = rdθ/dt + θdr/dt

v = rω + ωtdr/dt

v = (r + tdr/dt)ω

v = (r + tdr/dt)v'/r

v = v' + tv'/r(dr/dt)

v = v'[1 + t(dr/dt)/r]

Given that v' = 110 m/s, t = 33.0s, r = 120 m and dr/dt = rate at which line is shortened = -0.80 m/s (negative since it is decreasing)

So, v = 110 m/s[1 + 33.0 s(-0.80 m/s)/120 m]

v = 110 m/s[1 + 11.0 s(-0.80 m/s)/40 m]

v = 110 m/s[1 + 11.0 s(-0.02/s)]

v = 110 m/s[1 - 0.22]

v = 110 m/s(0.78)

v = 85.8 m/s

8 0
3 years ago
Other questions:
  • Consider this situation: Four ropes, each attached to the end
    5·1 answer
  • Four students measure the mass of a standard mass that has an accepted value of 150.0 g. They post their results in a table.
    15·1 answer
  • Explain quantum zeno effect in one sentence
    13·1 answer
  • A ball is launched vertically upward from the edge of a cliff. The ball reaches its maximum height 1.6 seconds after launch. Bar
    10·1 answer
  • A sound having a frequency of 395 Hz travels through air at 331 m/s. What is the wavelength of the sound? Answer in units of m.
    11·1 answer
  • I REALLY NEED HELP PLEASE!!! CAN SOMEONE ANSWER THIS? At 0 ºC, some amount of energy is required to change 1 kg of water from a
    10·2 answers
  • A metal ring 5.00 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpend
    7·1 answer
  • You are in a boat that is 1400 kg. The current is 1500N and is pushing you back. If you have an acceleration of 3 m/s^2 what is
    11·1 answer
  • What is the value of acceleration of a body if it is in uniform velocity​
    11·1 answer
  • The distance from the Moon to Earth is 3.9 x 10^8 meters. What is the time required for a light ray to travel from the Moon to E
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!