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
olga nikolaevna [1]
3 years ago
6

A kid drives 4 miles to the mall. If the speed limit is 45 miles/hr and the kid makes the trip in .03 hours. Is the kid breaking

the speed limit? a. No, he is going 1 mile/hr. b. Yes, he is going 133 miles/hr, C. No, he is going 40 miles/hr. d. Yes, he is going 150 miles/hr.
Physics
1 answer:
yuradex [85]3 years ago
7 0

Answer:B

Explanation:

.03 of an hr is 2 mins and if it takes 2 mins to drive 4 miles enter it in pace calulator you are going 120mph so the closest to 120 is 133mph

You might be interested in
Skater begins to spend with arms held out at shoulder height. The skater wants to match the speed of the spin to the beat of the
Aleksandr [31]

Answer:

the moment of inertia with the arms extended is Io and when the arms are lowered the moment

I₀/I > 1    ⇒   w > w₀

Explanation:

The angular momentum is conserved if the external torques in the system are zero, this is achieved because the friction with the ice is very small,

           L₀ = L_f

           I₀ w₀ = I w

          w =\frac{I_o}{I} w₀

where we see that the angular velocity changes according to the relation of the angular moments, if we approximate the body as a cylinder with two point charges, weight of the arms

          I₀ = I_cylinder + 2 m r²

where r is the distance from the center of mass of the arms to the axis of rotation, the moment of inertia of the cylinder does not change, therefore changing the distance of the arms changes the moment of inertia.

If we say that the moment of inertia with the arms extended is Io and when the arms are lowered the moment will be

        I <I₀

        I₀/I > 1    ⇒   w > w₀

therefore the angular velocity (rotations) must increase

in this way the skater can adjust his spin speed to the musician.

7 0
3 years ago
On a trip to the Colorado Rockies, you notice that when the freeway goes steeply down a hill, there are emergency exits every fe
Zanzabum

Answer:

The maximum speed that the truck can have and still be stopped by the 100m road is the speed that it can go and be stopped at exactly 100m. Since there is no friction, this problem is similar to a projectile problem. You can think of the problem as being a ball tossed into the air except here you know the highest point and you are looking for the initial velocity needed to reach that point. Also, in this problem, because there is an incline, the value of the acceleration due to gravity is not simply g; it is the component of gravity acting parallel to the incline. Since we are working parallel to the plane, also keep in mind that the highest point is given in the problem as 100m. Solving for the initial velocity needed to have the truck stop after 100m, you should find that the maximum velocity the truck can have and be stopped by the road is 18.5 m/s.

Explanation:

4 0
3 years ago
Can someone please help
Maru [420]

Answer: D

Explanation: because doing a yoga desk program is physical activity, 10k steps is pysical activity, riding a bike or walking/running is also physical activity. so it should be D, all of the above.

5 0
3 years ago
A sample of ore containing radioactive strontium 38Sr90 has an activity of 8.2 × 105 Bq. The atomic mass of strontium is 89.908
ahrayia [7]

From the activity values and the decay constant, the mass of of Strontium in the sample is:

1.62 × 10^{-7}g

<h3>What is the decay constant of an element?</h3>

The decay constant of an element is the probability of decay of a nucleus per unit time.

{λ = ln 2 / t1/2 

where;

t1/2 is the half-life of the isotope.

The half-life is converted to seconds since the decay constant is asked in per seconds.

28.8 years = 28.8 × 3.156 × 10^{7} = 908928000 s \\

Hence;

λ = \frac{ln2}{90892800s} = 7.626 s^{-1}

                                       

The activity of the element, A, the decay constant, λ and the number of nuclei, N are related as follows:

  • A = (–) λN

N = \frac{8.25 ×10^{5}}{7.626×10^{-10}} = 1.082 × 10^{15}              

Molar mass of Strontium-90 is 90 g.

1 mole of Strontium-90 contains 6.02×10^23 nuclei.

The mass, m of Strontium in the sample is calculated:

m = 1.082 × 10^{15} × \frac{90 g}{6.02 × 10^{23}} = 1.62 × 10^{-7}g \\

Therefore, the mass of of Strontium in the sample is:

1.62 × 10^{-7} \: g

Learn more about decay constant at: brainly.com/question/17159453

5 0
2 years ago
The hereditary material is known as
elena-s [515]
Genetic material<span>, also </span>known<span> as deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA)</span>
5 0
3 years ago
Other questions:
  • A pitcher throws a baseball as shown in the diagram below.
    9·2 answers
  • What method would you use to extract the salt from the salt water mixture?
    13·1 answer
  • How much heat is required to vaporize 1.5kg of liquid water at its boiling point
    10·1 answer
  • Carbon-14 is a naturally-occuring, stable isotope that is commonly used is scientific studies as a tracer and to date artifacts.
    13·2 answers
  • Two circuits have identical voltage sources. The only other elements in the circuits are resistors. The resistor in circuit A ha
    12·1 answer
  • A train traveled 280km in 3.5 hours. what was the average speed in m/s?
    7·1 answer
  • What are the 2 main parts of physical science
    15·1 answer
  • The ability of water molecules to form hydrogen bonds with other water molecules and water's ability to dissolve substances that
    10·1 answer
  • Why doesn't a transformer work with direct current? why is ac required?
    10·1 answer
  • Question 5
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!