All categories

3 years ago

Estimated speed of the vehicle

Physics

1 answer:

SSSSS [86.1K]3 years ago

3 0

Really, Gundy ? ! ?

The formula for the car's speed is given and discussed in the box. The formula is

v = √(2·g·μ·d)

Then they tell you that μ is 0.750 , and then they tell you that d = 52.9 m . Also, everybody knows that 'g' is gravity = 9.8 m/s² .

They also tell us that the mass of the car is 1,000 kg, and they tell us that it took 3.8 seconds to skid to a stop. But we already have all the numbers in the formula without knowing the car's mass or how long it took to stop. The police don't need to weigh the car, and nobody was there to measure how long the car took to stop. All they need is the length of the skid mark, which they can measure, and they'll know how fast the guy was going when he hit the brakes !

Now, can you take the numbers and plug them into the formula ? ! ?

v = √(2·g·μ·d)

v = √( 2 · 9.8 m/s² · 0.75 · 52.9 m)

v = √( 777.63 m²/s²)

v = 27.886 m/s

Rounded to 3 digits, that's 27.9 m/s .

That's about 62.4 mile/hour .

You might be interested in

A sinusoidal transverse wave of amplitude ym = 8.4 cm and wavelength = 5.3 cm travels on a stretched cord. Find the ratio of the

Scilla [17]

Answer:

The ratio is 9.95

Solution:

As per the question:

Amplitude, $y_{m} = 8.4\ cm$

Wavelength, $\lambda = 5.3\ cm$

Now,

To calculate the ratio of the maximum particle speed to the speed of the wave:

For the maximum speed of the particle:

$v_{m} = y_{m}\times \omega$

where

$\omega = 2\pi f$ = angular speed of the particle

Thus

$v_{m} = 2\pi fy_{m}$

Now,

The wave speed is given by:

$v = f\lambda$

Now,

The ratio is given by:

$\frac{v_{m}}{v} = \frac{2\pi fy_{m}}{f\lambda}$

$\frac{v_{m}}{v} = \frac{2\pi \times 8.4}{5.3} = 9.95$

8 0

3 years ago

A graph of angular position v. time has the following equation:

Harman [31]

Answer:

you can simply answer by derivative = 3.5x^2+25x+250-y=0 you can derivate this eqn 7x +25-1=0 7x=24 yo u can divide you get it

5 0

3 years ago

Two objects are placed in thermal contact and are allowed to come to equilibrium in isolation. The heat capacity of Object A is

Oksi-84 [34.3K]

Answer:

Explanation:

Heat capacity A = 3 x heat capacity of B

initial temperature of A = 2 x initial temperature of B

TA = 2 TB

Let T be the final temperature of the system

Heat lost by A is equal to the heat gained by B

mass of A x specific heat of A x (TA - T) = mass of B x specific heat of B x ( T - TB)

heat capacity of A x ( TA - T) = heat capacity of B x ( T - TB)

3 x heat capacity of B x ( TA - T) = heat capacity of B x ( T - TB)

3 TA - 3 T = T - TB

6 TB + TB = 4 T

T = 1.75 TB

8 0

3 years ago

where is the center of the universe located? and any 16 or older guys on here who are down to talk?? i got a pad we can talk on

bazaltina [42]

Answer:

the center of the universe is in your mom's stomach. why do I keep seeing people wanting to look for a date. the f. u. c. k.?

6 0

2 years ago

5. If one object has a greater speed than a second object. does the first necessarily have a greater acceleration? Explain, usin

Sveta_85 [38]

Answer:

Explanation:

5. not necessarily so that the first object could have left with initial velocity and the second not, so even if the second has a greater acceleration its velocity is less than that of the first

6. The acceleration of the motorcycle is

SI System Reductions

Vo = 80 km / h (1000m / 1km) (1h / 3600s) = 22.2 m / s

Vf = 90 km / h (1000m / 1km) (1h / 3600s) = 25 m / s

Vf = Vo + at at = Vf-Vo

am = (Vf-Vo) / t

am = (25 -22.2) / t = 2.8 / t

am= 2.8/t

For the bike we have

Vf = 10 km / h (1000m / 1km) (1h / 3600s) = 2.78 m / s

Vo = 0

ab = (Vf -Vo) / t

ab = (2.78 -0) / t

ab = 2.8/t

Since time is the same for both of us, if we round to Significant figures the two accelerations are equal

7. If when an object is slowing or slowing down.

For example, a car goes north and must stop at the traffic light, the acceleration of the brakes goes south

8. Yes, since an object can go to the left and the acceleration to the right, but the object will lose speed over time

9. in the launch of projectiles the acceleration is negative and the speed after half the path is also negative

10. Car B must be moving to car A, because if they leave together B has more acceleration, bone that travels the distance at the same time

11. When we have friction, the velocity of an object increases by an external force, but the friction also increases the acceleration, but since it is positive, the velocity increases until the acceleration is zero and hence the velocity remains constant.

8 0

3 years ago