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
Simora [160]
3 years ago
15

Calculate the activity of 60Co after 72hr, if you know the activity at time 0 is 35MBq (decay constant=0.001 day-1)?

Physics
1 answer:
Marianna [84]3 years ago
4 0

Answer:

The activity of cobalt-60 after 72 hours is 34.895 MBq

Explanation:

A(t) = Ao(0.5)^t/t1/2

A(t) is the activity of cobalt-60 after time t

Ao is the initial activity of cobalt-60 = 35 MBq

t is time taken to reduce in activity = 72 hours = 72/24 = 3 days

t1/2 is the half-life = 0.693 ÷ decay constant = 0.693 ÷ 0.001/day = 693 days

A(72) = 35(0.5)^3/693 = 35 × 0.5^0.00433 = 35 × 0.997 = 34.895 MBq

You might be interested in
What is the wavelength of a sound wave traveling at 360 m/s and a
3241004551 [841]

Answer:2.4m

Explanation:

Velocity=360m/s

Frequency=150Hz

Wavelength=velocity ➗ frequency

Wavelength=360 ➗ 150

Wavelength=2.4m

8 0
3 years ago
Air that enters the pleural space during inspiration but is unable to exit during expiration creates a condition called a. open
sertanlavr [38]

Answer:

The correct answer is d. tension pneumothorax.

Explanation:

The increasing build-up of air that is in the pleural space is what we call the tension pneumothorax and this happens due to the lung laceration that lets the air to flee inside the pleural space but it does not return.

4 0
3 years ago
A car starts from rest and acquires a velocity of 50m/s in 3secs. Calculate i) acceleration ii) distance covered.
mafiozo [28]

Answer: 75.02 m

Explanation:

u = 0 ( starts from rest )

v = 50 m/s

t = 3 s

( i ) a = v - u / t

= 50 - 0 /3

= 16.67

( ii ) s = ut + 1/2 at²

= 0 × 3 + 1/2 × 16.67 × 3 × 3

= <u>75.02 m</u>

Hope this helps...

4 0
3 years ago
Care sunt marimile ce caracterizează nucleul?
Yakvenalex [24]

Answer:

Sub stratul exterior lichid-metal al miezului Pământului se află o bilă solidă de fier și aliaj de nichel cu aproximativ 1,60 km în diametru.

Explanation:

4 0
3 years ago
A car travels from Boston to Hartford in 4 hours. The two cities are 240 kilometers apart. What was the average speed of the car
Y_Kistochka [10]

Answer:

Average speed is 60 km/hour

Explanation:

When we need to calculate average speed, we use this equation:

V = \frac{x_{f} - x_{o}}{t_{f} - t_{o}}

Where:   x_{o} = 0 km   position at the beginning

              x_{f} = 240 km   at the end

              t_{o} = 0 hours

              t_{f} = 4 hours

Then:     V = \frac{240 km - 0 km}{4 hours - 0 hours}

              V = \frac{240 km}{4 hours}

Finally    V = 60 km/hour

6 0
3 years ago
Other questions:
  • a paraellel plate capacitor consists of 2 large circular sheets of metal separated by 1.53 cm. The electric field energy density
    9·1 answer
  • The equation for distance is d = st. If a car has a speed of 77.0 m/s and travels for 45.0 seconds, how far does it go?
    6·2 answers
  • This term means pertaining to or exist at or from the very beginning.
    6·1 answer
  • Without understanding mathematics, it is practically impossible to see its applicability and beauty
    11·1 answer
  • If two similar large plates each of area having surface charge density is +a and -b are separated by a distance d in air find th
    10·1 answer
  • Write a paragraph of no less than five sentences explaining how Newton's First Law of Motion supports people's need to wear seat
    12·1 answer
  • Hiking with 10-15 lb backpack can increase your calorie burn by how much
    9·1 answer
  • A tray containing 0.20kg of water at 20degree celsius is placed in a freezer. The temperature of the water drops to 0degree cels
    14·2 answers
  • What is the kinetic energy of a jogger with a mass of 70.8 kg traveling at a speed of 2.4 m/s?
    11·1 answer
  • are the two sources in phase or out of phase? explain how you can tell from the diagram. if the two sources are out of phase, gi
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!