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
Oksanka [162]
3 years ago
14

ear the end of a marathon race, the first two runners are separated by a distance of 45.0 m. The front runner has a velocity of

3.45 m/s, and the second a velocity of 4.25 m/s. (a) What is the velocity (in m/s) of the second runner relative to the first? m/s faster than the front runner (b) If the front runner is 250 m from the finish line, who will win the race, assuming they run at constant velocity? The first runner will win. The second runner will win. (c) What distance (in m) ahead will the winner be when she crosses the finish line? m
Physics
2 answers:
sesenic [268]3 years ago
6 0

Answer:

a) V_{2/1}=0.8m/s

b) The second runner will win

c) d = 10.54m

Explanation:

For part (a):

V_{2/1} = V_{2} - V_{1} = 0.8m/s

For part (b) we will calculate the amount of time that takes both runners to cross the finish line:

t_{1} = \frac{X_{1}}{V_{1}}=\frac{250}{3.45}=72.46s

t_{2} = \frac{X_{2}}{V_{2}}=\frac{250+45}{4.25}=69.41s

Since it takes less time to the second runner to cross the finish line, we can say the she won the race.

For part (c), we know how much time it takes the second runner to win, so we just need the position of the first runner in that moment:

X1 = V1*t2 = 239.46m  Since the finish line was 250m away:

d = 250m - 239.46m = 10.54m

SpyIntel [72]3 years ago
4 0

Answer:

At the time t = 0, the distance is 45m

the front runer has a velocity of 3.45 m/s, the second one has a velocity of 4.25 m/s

then the position of both runes, puting the zero of the position where the runer 1 is:

p1(t) = (3.45m/s)*t

p2(t)= (4.25m/s)*t - 45m

a) relative velocity: this is the differenceof both velocities: v2 - v1 = 4.25m/s - 3.45m/s = 0.8m/s

this means that the first runner sees the second one with a positive velocity.

b) if the first runner is 250m away from the finish line, then:

the first runner needs:

p1(t) = 250m = (3.45m/s)*t

t = (250/3.45) s = 72.5 seconds

for the runner 2

p2(t) = 250m = (4.25m/s)*t - 45m

250m + 45m = 295m = (4.25m/s)*t

(295/4.25) s = t = 69.4 seconds

So the runner 2 needs less time, this means that he will reach the finish line first

c) we know that at t= 69.4 seconds, the second runner is in the finish line, we can imput that thime in the position of the runner 1:

p1(69.4s) = (3.45m/s)*69.4s = 239.5m

and at this time, the runner 2 is already at the finish line that was 250m away from the first runner, so the distance is:

250m - 239.5m = 10.5m

You might be interested in
Noble Gases do not readily form compounds because they ___ chemically stable with 8 valence electrons
azamat

Answer : Noble Gases do not readily form compounds because they are chemically stable with 8 valence electrons.

Explanation :

Noble gases are the chemical elements that are present in group 18 in the periodic table.

The elements are helium, neon, argon, krypton, xenon and radon.

They are chemically most stable except helium due to having the maximum number of 8 valence electrons can hold their outermost shell that means they have a complete octet.

They are rarely reacts with other elements to form compounds by gaining or losing electrons since they are already chemically stable.

Hence, the noble Gases do not readily form compounds because they are chemically stable with 8 valence electrons.

8 0
3 years ago
Hydrogen bonds are too weak to bind atoms together to form molecules, but they do hold different parts of a single large molecul
pogonyaev

Hydrogen bonds are too weak to bind atoms together to form molecules, but they do hold different parts of a single large molecule in a specific three-dimensional shape. The given statement is true.

<h3>What are hydrogen bonds?</h3>

A hydrogen bond is an electrostatic force of attraction among a hydrogen atom tightly attached to a more electronegative "donor" atom or group and another electronegative atom bearing a lone pair of electrons, known as the hydrogen bond acceptor.

Hydrogen bonds are too flimsy to connect atoms to form molecules, but they do hold various portions of a single large molecule together in a specific three-dimensional shape.

Thus, the given statement is true.

For more details regarding hydrogen bonding, visit:

brainly.com/question/10904296

#SPJ1

5 0
1 year ago
During a single-replacement reaction, a more-active metal will replace a less-active metal in a compound. Which single-replaceme
son4ous [18]

Answer:

Mg will replace Ag in a compound

Explanation:

A single replacement reaction is driven by the position of ions on the activity series.

As a rule of thumb, the position of metal ions on the activity series determines their reactivity.

Metal ions that are above another are more reactive and they will displace those that are lower.

Generally, activity increases as we go up the group.

Mg ions are higher than Ag ions on the series so, Mg will displace Ag from a solution.

8 0
3 years ago
When the core of a star like the sun uses up its supply of hydrogen for fusion, the core begins to ________?
pav-90 [236]

When the core of a star like the sun uses up its supply of hydrogen for fusion, the core begins to contract in size. The gravitational forces becomes strong and cause the star to reduce in size. as the star contracts, the temperature of the star also rises since the heat is distributed inside smaller Volume now.

4 0
3 years ago
Read 2 more answers
The sun is part of which type of galaxy?
jeka94
I believe the answer is D. The milky way is a spiral galaxy, You can tell just by looking at it.
4 0
3 years ago
Other questions:
  • A battery powers a circuit for a small noisy fan. The fan’s motor gets warm as it turns. What energy transformations are taking
    6·2 answers
  • Why should you explore the potential roadblocks to your chosen career?
    13·1 answer
  • Through which Earth layer are S waves not transmitted?
    12·2 answers
  • You drop a rock off a bridge. When the rock has fallen 4 m, you drop a second rock. As the two rocks continue to fall, what happ
    10·1 answer
  • Three remote control cars are identical size and weight. The motors installed in the three cars are 100 watts, 150 watts and 200
    7·1 answer
  • Your mass is 65 kg. you stand on a bathroom scale in an elevator on earth. (a) what force would the scale exert when the elevato
    14·1 answer
  • Please help with this :(
    7·1 answer
  • Raghu studies in grade 6th. He wants a cricket bat to be made by a carpenter. He tells the
    14·1 answer
  • Aball is thrown horizontaly from the top of a building with an initial velocity of 15 meters per second. At the same instant, a
    7·1 answer
  • I’m sorry, but the person you are calling has a voice mailbox that has not been set up yet.
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!