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
Anna11 [10]
3 years ago
14

The half-life of a certain isotope is 15 minutes. How much of a 400 g sample will remain after 90 minutes?12.5 g6.25 g26.7 g66.7

g25 g
Physics
1 answer:
Virty [35]3 years ago
4 0

There is a total of 6 half lives that need to take place.


ONE HALF LIFE = 200

TWO HALF LIFES = 100

THREE HALF LIFES  = 50

FOUR HALF LIFES = 25

FIVE HALF LIFES = 12.5

SIX HALF LIFES = 6.25


The answer is 6.25g



You might be interested in
Assume a satellite shines an unpolarized light on a telescope. The intensity of the light as it reaches the telescope is 1.1*10-
n200080 [17]

Answer:

4.125\times 10^{-11}\ W/m^2

Explanation:

I_0 = Intensity of unpolarized light = 1.1\times 10^{-10}\ W/m^2

\theta = Angle of the filter = 30^{\circ}

Intensity of light is given by

I=\dfrac{I_0}{2}cos^2\theta\\\Rightarrow I=\dfrac{1.1\times 10^{-10}}{2}cos^230\\\Rightarrow I=4.125\times 10^{-11}\ W/m^2

The intensity of light detected by the camera is 4.125\times 10^{-11}\ W/m^2

7 0
3 years ago
On the moon, the acceleration due to gravity is one-sixth that of earth. That is gmoon = gearth /6 = (9.8 m/s2 )/6 = 1.63 m/s2 .
MAVERICK [17]
The pendulum would differ from 300 inches
8 0
2 years ago
Water, H2O ,and methane ,CH4, are both covalent substances . why is water a liquid at room temperature while methane is a gas ?
stiv31 [10]
I think the answer is b
7 0
2 years ago
Read 2 more answers
The energies of electrons are said to be quantized. Explain what this means. please explain.
sleet_krkn [62]
To move from one energy<span> level to another, an </span>electron<span> must gain or lose just the right amount of </span>energy<span>. </span>Electrons are said to be quantized<span> because they need a quantum of </span>energy<span> to move to a different sublevel. ... When atoms absorb </span>energy<span>, </span>electrons<span> move into higher </span>energy<span> levels.</span>
8 0
3 years ago
A 0.750 kg block is attached to a spring with spring constant 17.5 N/m. While the block is sitting at rest, a student hits it wi
Dmitriy789 [7]

Answer:

a

 A =  0.081 \  m

b

The value is  u =  0.2569 \  m/s

Explanation:

From the question we are told that

   The mass is  m  =  0.750 \ kg

   The spring constant is  k  =  17.5 \  N/m

    The instantaneous speed is  v  =  39.0 \  cm/s= 0.39 \  m/s

    The position consider is  x =  0.750A  meters from equilibrium point

   

Generally from the law of  energy conservation we have that

        The kinetic energy induced by the hammer  =  The energy stored in the spring

So

          \frac{1}{2} *  m * v^2  =  \frac{1}{2}  *  k  *  A^2

Here a is the amplitude of the subsequent oscillations

=>      A =  \sqrt{\frac{m *  v^ 2 }{ k} }

=>      A =  \sqrt{\frac{0.750 *  0.39 ^ 2 }{17.5} }

=>       A =  0.081 \  m

Generally from the law of  energy conservation we have that

The kinetic energy  by the hammer  =  The energy stored in the spring at the point considered   +   The kinetic energy at the considered point

             \frac{1}{2}  * m *  v^2 = \frac{1}{2}  * k x^2 + \frac{1}{2}  * m *  u^2

=>          \frac{1}{2}  * 0.750 *  0.39^2 = \frac{1}{2}  * 17.5* 0.750(0.081 )^2 + \frac{1}{2}  * 0.750 *  u^2

=>          u =  0.2569 \  m/s

3 0
2 years ago
Other questions:
  • Which characteristic of the planets in our solar system increases as the distance from the sun increase?
    8·1 answer
  • If the core of a supernova contains about one solar mass, the core will become a
    7·2 answers
  • Which statement is true about a farsighted (hyperopic) eye?
    12·1 answer
  • There are six books in a stack, and each book weighs 5 N. The coefficient of static friction between the books is 0.2. With what
    9·2 answers
  • its a hot day at the beach you look at your portable themometer which says its 30°C. what is the temperature in Fahrenheit and K
    12·2 answers
  • You are leading a software development team which uses serverless computing with AWS Lambda to build and run applications withou
    9·1 answer
  • Use dominant trait in a sentence
    14·1 answer
  • A tennis ball moving at a speed of 4 m/s, collides with a bowling ball at rest. The tennis ball bounces back in the direction op
    12·1 answer
  • A quantity that is fully described by magnitude alone is a ___________ quantity. A quantity that is fully described by both magn
    11·1 answer
  • Nicki rides her bike at a constant speed for 6 km. That part of her ride takes her 1 h. She then rides her bike at a constant sp
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!