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
andrezito [222]
1 year ago
6

A bike race against the clock takes place on a straight road. Yan drives at 37 km / h and he starts the course 30s before Christ

ophe. Christophe is traveling at 38.9 km / h.A) How long after Yan's departure will Christophe join him?B) How far from the start will Christophe join Yan?
Physics
1 answer:
joja [24]1 year ago
3 0

Given data:

Yan speed;

u_1=37\text{ km/h}

Christopher speed;

u_2=38.9\text{ km/h}

Christophe starts 30 s later than Yan. Therefore, Christophe takes 30 s less than Yan to reach the same distance.

Part (A)

The distance is given as,

d=ut

Let both Yan and Christophe meet at d distance from the start position. Therefore,

u_1t=u_2(t-30)

Substituting all known values,

\begin{gathered} (37\text{ km/h})t=(38.9\text{ km/h})\times(t-30) \\ \frac{(37\text{ km/h})}{(38.9\text{ km/h})}=\frac{(t-30)}{t} \\ 0.95=1-\frac{30}{t} \\ \frac{30}{t}=1-0.95 \\ \frac{30}{t}=0.05 \\ t=\frac{30}{0.05} \\ t=600\text{ s} \end{gathered}

Therefore, 600 s after Yan's departure Christophe will join him.

Part (B)

The distance is given as,

d=u_1t

Substituting all known values,

\begin{gathered} d=(37\text{ km/h})\times(600\text{ s}) \\ =(37\text{ km/h})\times(600\text{ s})\times(\frac{1\text{ hr}}{3600\text{ s}}) \\ \approx6.17\text{ km} \end{gathered}

Therefore, Christophe joins Yan after 6.17 km from the start.

You might be interested in
A rocket has a mass 250 x (10^3) slugs on earth. Specify(a) its mass in SI units, and(b)its weight in SI units.If the rocket is
zloy xaker [14]

Explanation:

It is given that,

Mass of the rocket, m=250\times 10^3\ slugs

(a) The SI unit of mass is kilogram (kg). The relation between slugs and the kg is given by :

1 slug = 14.59 kg

So, 250\times 10^3\ slugs=250\times 10^3\times 14.59

Mass of the rocket, m = 3647500 kg

(b) Weight of the rocket is given by :

W = m g

W=3647500\times 9.8=35745500\ N

or

W=3.5\times 10^7\ N

(c) If the rocket is placed on the moon. The acceleration due to gravity on the moon is, a=5.3\ ft/s^2=1.61\ m/s^2

Mass is the amount of matter contained inside the object. So, the mass of the rocket remains the same i.e. 3647500  kg

Weight of the rocket on the moon is, W=mg

W=3647500\times 1.61

W = 5872475 N

or

W=5.8\times 10^6\ N

Hence, this is the required solution.                        

8 0
3 years ago
Which one is NOT an application of heating effect of electric current ? * Required to answer. Single choice.(1 Point) Electric b
solmaris [256]

Answer:

Electromagnet.

Explanation:

Electric bulb and electric water heather are application of heating effect of electric current. The electromagnet is not the result of heating effect of electric current. The bulb gives light due to the heating effect similarly the water is heated or warmed by the heating effect of electric current.

5 0
3 years ago
A car is travelling at a speed of 30 m/s. It decelerates at a rate of 12 m/s^2. Calculate the time taken for the car to come to
user100 [1]

Answer:

The answer to your question is: t = 2.5 s

Explanation:

Data

vo = 30 m/s

a = -12 m/s2

t = ?

vf = 0 m/s

Formula

vf = vo + at

Substitution

                              0 m/s = 30 + (-12)t

Solve it for t           -30 = -12t

                              t = -30 / -12

                              t =  30/12  = 15/6 = 5/2

                              t = 2.5 s                              

8 0
3 years ago
Read 2 more answers
Which one of the following statements indicates the result of Kepler's astronomical calculations?
garri49 [273]
The correct answer for the question that is being presented above is this one: "<span>c. Planets orbit in elliptical patterns; a planet's orbit covers equal areas in equal amounts of time; planets' orbits are shorter or longer depending on their distance from the Sun."</span>

Here are the following choices:
a. Planets orbit in elliptical patterns; the bigger the planet, the more gravitational pull; a planet's gravitational pull is stronger or weaker depending on its distance from the Sun.

b. A planet's orbit covers equal distances in equal amounts of time; the speed of a planet's orbit depends on its distance from the Sun; the bigger the planet, the slower it moves.

c. Planets orbit in elliptical patterns; a planet's orbit covers equal areas in equal amounts of time; planets' orbits are shorter or longer depending on their distance from the Sun.
5 0
3 years ago
How many justified by Bohr model?
Dominik [7]

X-ray formation

Energy difference in the first ionization of the same group of elements

Differential linear emission spectra of different elements

Explanation:

The formation of x-ray, energy difference in the first ionization of the same group of elements and differential linear emission spectra of different elements can be justified by the Bohr model of the atom.

  • According to Neil Bohr, in an atom, the extranuclear part consists of electrons in specific spherical orbits around the nucleus.
  • Bohr's model explained the discrete lines in atomic spectrum of different elements.
  • Due to excitation of electrons, some rays are given off. Some of these are energetic like x-rays.
  • The energy difference between the first ionization of the same group of elements is a proof that electrons are in specific spherical orbits.
  • The higher the energy the level, the ease at which electrons can be removed and the lower the ionization energy.

Learn more:

Bohr model of the atom brainly.com/question/4986277

#learnwithBrainly

3 0
4 years ago
Other questions:
  • A 10 kg bicycle is traveling at a speed of 2 ms what is the bikes kinetic energy
    11·1 answer
  • Someone please help with the picture up top??
    10·1 answer
  • A dog sits 1.22 m from the center of a merrygo-round with an angular speed of 1.07 rad/s. If the magnitude of the force that mai
    8·1 answer
  • Which of these is a type of mass movement that is likely to happen after a large amount of rain
    10·2 answers
  • A physical quantity X is connected from X = ab2/C. Calculate percentage error in X, when percentage error in a,b,c are 4,2 and 3
    5·1 answer
  • A missile is moving 1350 m/s at a 25.0° angle. It needs to hit a target 23,500 m away in a 55.0° direction in 10.20 s. What is d
    11·1 answer
  • During the _____ collision, the vehfirst second third fourthicle comes to an abrupt stop.
    7·1 answer
  • An 100 V/m electric field is directed along the x axis. If the potential at the origin is 300 V, what is potential at the point
    9·2 answers
  • 100! BRAINLY!!!!!!!!
    12·1 answer
  • Quincy has cancer and is having to take chemotherapy treatments that make him very ill after the treatment. A month ago, after h
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!