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
Gennadij [26K]
3 years ago
14

If a subway train is moving to the left (has a negative velocity) and then comes to a stop, what is the direction of its acceler

ation? Is the acceleration positive or negative?
Physics
1 answer:
Katen [24]3 years ago
8 0

Answer:

The acceleration would be positive, pointing to the right.

Explanation:

The acceleration tells us how velocity changes every second. If the train stops, this means its velocity must go from a non-zero value to zero.

To reduce velocity, acceleration must point to the opposite direction. Since velocity is negative, acceleration must be positive.

You might be interested in
Formation of hydrogen bonds requires hydrogen atoms and what else?
ohaa [14]

Answer:

either a Nitrogen atom, Oxygen atom, or a Flourine atom

Explanation:

The atom has to be more electronegative than hydrogen for the bond to form.

8 0
3 years ago
A certain first-order reaction is 58% complete in 95 s. What are the values of the rate constant and the half-life for this proc
guajiro [1.7K]

Answer:

0.005734 s^{-1} and 20.86 seconds are the values of the rate constant and the half-life for this process respectively..

Explanation:

Expression for rate law for first order kinetics is given by:

a_o=a\times e^{-kt}

where,

k = rate constant  

t = age of sample

a_o = let initial amount of the reactant  

a = amount left after decay process  

We have :

a_o=x

a=58\%\times x=0.58x

t = 95 s

0.58x=x\times e^{-k\times 95 s}

\k= 0.005734 s^{-1}

Half life is given by for first order kinetics::

t_{1/2}=\frac{0.693}{k}

=\frac{0.693}{0.005734 s^{-1}}=120.86 s

0.005734 s^{-1} and 20.86 seconds are the values of the rate constant and the half-life for this process respectively..

3 0
3 years ago
If there is no oxygen in outer space, and, at the same time, oxygen must be present for fire, where does the sun come from?​
victus00 [196]

The sun is a huge ball of gas held together by gravity.

It does not burn the way wood does, due to oxygen, but it gets energy by a process called nuclear fusion, where Hydrogen is converted to Helium.

The sun will cease to "burn" when it runs out of Hydrogen, but that has a long way to go.

3 0
3 years ago
Read 2 more answers
A taxi is travelling at 15m/s. Its driver accelerates with acceleration 3m/s^2 for 4 s. What would be the new velocity?..... pls
Aleksandr-060686 [28]

Answer:

27 m/s

Explanation:

Given:

v₀ = 15 m/s

a = 3 m/s²

t = 4 s

Find: v

v = at + v₀

v = (3 m/s²) (4 s) + (15 m/s)

v = 27 m/s

5 0
3 years ago
Read 2 more answers
Which is one way scientists indicate how precise and accurate there experimental measurements are
kherson [118]
They do the method 3 times to be sure. Because if you do it once, that could mean anything. If you do it twice, it may or may not have the same result. If you do it 3 times and it matches one of the previous answers, then it's likely that it's correct.
8 0
3 years ago
Other questions:
  • A 0.25-m string, vibrating in its sixth harmonic, excites a 0.96-m pipe that is open at both ends into its second overtone reson
    5·1 answer
  • A squirrel (mass 0.9 kg) is running across the road at a speed 4.0 m/s. What is the
    7·2 answers
  • "what is the period of one vibration of this tone?"
    13·1 answer
  • A 250 mL sample of nitrogen(N2) has a pressure of 745 mm Hg at 30 C.What is the mass of nitrogen?
    5·1 answer
  • The girl is using her arm to lift a weight. Her arm is acting as a _______.
    9·2 answers
  • The acceleration of the body in the graph given below is____
    12·1 answer
  • A woman is riding a bicycle at 18.0 m/s along a straight road that runs parallel to and right next to some railroad tracks. She
    9·1 answer
  • Which of the following is the correct definition of light energy?
    14·1 answer
  • Hii please help i’ll give brainliest!!
    7·1 answer
  • If mason runs a 5 k race at an average speed of 300 m/min how long will it take him to finish
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!